LV 14360
LV 14360
LV14360 60-V, 3-A Step-Down Converter With High Light Load Efficiency
1 Features                                                                 3 Description
•     4.3-V to 60-V input range                                            The LV14360 is a 60-V, 3-A step-down regulator with
•     3-A continuous output current                                        an integrated high-side MOSFET. With a wide input
•     300-µA operating quiescent current                                   range from 4.3 V to 60 V, the device is suitable
•     155-mΩ high-side MOSFET                                              for various applications from industrial to automotive
•     Current mode control                                                 for power conditioning from unregulated sources.
•     Adjustable switching frequency from 200 kHz to 2                     The quiescent current of the regulator is 300 µA in
      MHz                                                                  sleep mode, which is suitable for battery-powered
•     Frequency synchronization to external clock                          systems. An ultra-low 1-μA current in shutdown mode
•     Internal compensation for ease of use                                can further prolong battery life. A wide adjustable
•     High duty cycle operation supported                                  switching frequency range allows either efficiency or
•     Precision enable input                                               external component size to be optimized. Internal
•     1-µA shutdown current                                                loop compensation means that the user is free
•     Thermal, overvoltage, and short protection                           from the tedious task of loop compensation design.
•     8-pin HSOIC with PowerPAD™ package                                   This also minimizes the external components of the
                                                                           device. A precision enable input allows simplification
2 Applications                                                             of regulator control and system power sequencing.
•     Industrial power supplies                                            The device also has built-in protection features such
•     Communications equipment and datacom modules                         as cycle-by-cycle current limit, thermal sensing and
•     General purpose wide VIN regulation                                  shutdown due to excessive power dissipation, and
                                                                           output overvoltage protection.
                                                                           The LV14360 is available in an 8-pin, 4.89-mm ×
                                                                           3.9-mm HSOIC package with exposed pad for low
                                                                           thermal resistance.
                                                                                                             Device Information
                                                                                             PART NUMBER          PACKAGE(1)          BODY SIZE (NOM)
                                                                                               LV14360               HSOIC            4.89-mm × 3.9-mm
                                                      L
                                                                    VOUT                      60
                     RT/SYNC          SW
                                                                                              50
             RT                               D           RFBT
                                                                                              40
                                                                   COUT
                                                                                              30
                     SS                FB                 RFBB
         CSS                                                                                  20                                            VIN = 12 V
                               GND                                                                                                          VIN = 24 V
                                                                                              10
                                                                                                                                            VIN = 48 V
                                                                                               0
                                                                                              0.0001      0.001      0.01      0.05   0.2   0.5 1   2 3
     Simplified Schematic For Soft-Start (SS) Option                                                                  IOUT (A)                           D012
         An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
         intellectual property matters and other important disclaimers. PRODUCTION DATA.
LV14360
SNVSAZ1A – AUGUST 2017 – REVISED SEPTEMBER 2020                                                                                                                  www.ti.com
                                                                        Table of Contents
1 Features............................................................................1     8.3 Feature Description...................................................10
2 Applications..................................................................... 1       8.4 Device Functional Modes..........................................16
3 Description.......................................................................1     9 Application and Implementation.................................. 17
4 Revision History.............................................................. 2          9.1 Application Information............................................. 17
5 Device Comparison Table...............................................2                   9.2 Typical Application.................................................... 17
6 Pin Configuration and Functions...................................3                     10 Power Supply Recommendations..............................23
  Pin Functions.................................................................... 3     11 Layout........................................................................... 23
7 Specifications.................................................................. 4        11.1 Layout Guidelines................................................... 23
  7.1 Absolute Maximum Ratings........................................ 4                    11.2 Layout Example...................................................... 24
  7.2 ESD Ratings............................................................... 4        12 Device and Documentation Support..........................25
  7.3 Recommended Operating Conditions.........................4                            12.1 Receiving Notification of Documentation Updates..25
  7.4 Thermal Information....................................................5              12.2 Support Resources................................................. 25
  7.5 Electrical Characteristics.............................................5              12.3 Trademarks............................................................. 25
  7.6 Switching Characteristics............................................6                12.4 Glossary..................................................................25
  7.7 Typical Characteristics................................................ 7             12.5 Electrostatic Discharge Caution..............................25
8 Detailed Description........................................................9           13 Mechanical, Packaging, and Orderable
  8.1 Overview..................................................................... 9       Information.................................................................... 25
  8.2 Functional Block Diagram......................................... 10
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision * (August 2017) to Revision A (September 2020)                                                                                         Page
• First public release..............................................................................................................................................1
• Updated the numbering format for tables, figures and cross-references throughout the document...................1
BOOT 1 8 SW
                                           VIN              2                      7             GND
                                                                 Thermal Pad
                                                                     (9)
                                             EN             3                      6             SS or PGOOD
RT/SYNC 4 5 FB
Pin Functions
                PIN
                                      TYPE (1)                                            DESCRIPTION
 NO.                NAME
                                                  Bootstrap capacitor connection for high-side MOSFET driver. Connect a high quality 0.1-μF
 1                  BOOT                 P
                                                  capacitor from BOOT to SW.
                                                  Connect to power supply and bypass capacitors CIN. Path from VIN pin to high frequency
 2                    VIN                P
                                                  bypass CIN and GND must be as short as possible.
                                                  Enable pin with internal pullup current source. Pull below 1.2 V to disable. Float or connect to
 3                    EN                 A
                                                  VIN to enable. Adjust the input undervoltage lockout with two resistors (see Section 8.3.6).
                                                  Resistor timing or external clock input. An internal amplifier holds this pin at a fixed voltage
                                                  when using an external resistor to ground to set the switching frequency. If the pin is
                                                  pulled above the PLL upper threshold, a mode change occurs and the pin becomes a
 4                RT/SYNC                A
                                                  synchronization input. The internal amplifier is disabled and the pin is a high impedance clock
                                                  input to the internal PLL. If clocking edges stop, the internal amplifier is re-enabled, and the
                                                  operating mode returns to frequency programming by resistor.
                                                  Feedback input pin, connect to the feedback divider to set VOUT. Do not short this pin to
 5                    FB                 A
                                                  ground during operation.
                     SS                           SS pin for soft-start version, connect to a capacitor to set soft-start time.
 6                   or                  A        The PGOOD pin for power-good version, open-drain output for power-good flag, use a 10-kΩ
                   PGOOD                          to 100-kΩ pullup resistor to logic rail or other DC voltage no higher than 7 V.
 7                    GND                G        System ground pin
                                                  Switching output of the regulator. Internally connected to high-side power MOSFET. Connect
 8                    SW                 P
                                                  to power inductor.
 9              Thermal Pad              G        Major heat dissipation path of the die. Must be connected to ground plane on PCB.
7 Specifications
7.1 Absolute Maximum Ratings
Over the recommended operating junction temperature range of –40°C to +125°C (unless otherwise noted)(1)
                                                                                                  MIN                     MAX              UNIT
                               VIN, EN to GND                                                     –0.3                     65
                               BOOT to GND                                                        –0.3                     71
                               SS to GND                                                          –0.3                      5
    Input voltages                                                                                                                             V
                               FB to GND                                                          –0.3                      7
                               RT/SYNC to GND                                                     –0.3                     3.6
                               PGOOD to GND                                                       –0.3                      7
                               BOOT to SW                                                                                  6.5
    Output voltages                                                                                                                            V
                               SW to GND                                                           –3                      65
    Junction temperature, TJ                                                                      –40                     150                  °C
    Storage temperature, Tstg                                                                     –65                     150                  °C
(1)      Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress
         ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under
         Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device
         reliability.
(1)      JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
(2)      JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
(1)      Operating Ratings indicate conditions for which the device is intended to be functional, but do not ensure specific performance limits.
         For ensured specifications, see Section 7.5.
(1)     For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
        report.
(2)     Power rating at a specific ambient temperature TA should be determined with a maximum junction temperature (TJ) of 125°C (see
        Section 7.3).
Limits apply over the recommended operating junction temperature (TJ) range of –40°C to +125°C, unless otherwise stated.
Minimum and maximum limits are specified through test, design or statistical correlation. Typical values represent the most
likely parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless otherwise specified, the following
conditions apply: VIN = 4.3 V to 60 V
                      PARAMETER                                      TEST CONDITIONS                      MIN          TYP        MAX UNIT
    VOLTAGE REFERENCE (FB PIN)
                      Feedback voltage                   TJ = 25°C                                       0.746         0.75      0.754     V
    VFB
                                                         TJ = –40°C to 125°C                             0.735         0.75      0.765     V
    HIGH-SIDE MOSFET
    RDS_ON            On-resistance                      VIN = 12 V, BOOT to SW = 5.8 V                                 155        320    mΩ
    HIGH-SIDE MOSFET CURRENT LIMIT
    ILIMT             Current limit                      VIN = 12 V, TA = 25°C, Open Loop                   3.8        4.75         5.7    A
    THERMAL PERFORMANCE
    TSHDN             Thermal shutdown threshold                                                                        170
                                                                                                                                           °C
    THYS              Hysteresis                                                                                         12
100 100
90 90
                                80                                                                                                   80
             Efficiency (%)
                                                                                                  Efficiency (%)
                                70                                                                                                   70
60 60
50 50
                                                                            VIN = 12 V                                                                                                    VIN = 36 V
                                40                                          VIN = 18 V                                               40                                                   VIN = 48 V
                                                                            VIN = 24 V                                                                                                    VIN = 60 V
                                30                                                                                                   30
                                 0.001            0.01           0.1          1          3                                            0.001             0.01                0.1               1         3
                                                          IOUT (A)                       D001
                                                                                                                                                                     IOUT (A)                           D002
VOUT = 3.3 V ƒSW = 500 KHz VOUT = 3.3 V ƒSW = 500 KHz
                               Figure 7-1. Efficiency vs Load Current                                                               Figure 7-2. Efficiency vs Load Current
                              100                                                                                                   100
90 90
                               80                                                                                                    80
            Efficiency (%)
Efficiency (%)
70 70
60 60
50 50
                                                                            VIN = 12 V                                                                                                    VIN = 36 V
                               40                                           VIN = 18 V                                               40                                                   VIN = 48 V
                                                                            VIN = 24 V                                                                                                    VIN = 60 V
                               30                                                                                                    30
                                0.001             0.01           0.1          1          3                                            0.001             0.01                0.1               1         3
                                                          IOUT (A)                       D003
                                                                                                                                                                     IOUT (A)                           D004
                               Figure 7-3. Efficiency vs Load Current                                                               Figure 7-4. Efficiency vs Load Current
                               0.2                                                                                                  125
                                                                                                                                                VFB Falling
                              0.15                                                                                                              VFB Rising
                                                                                                  Nominal Switching Frequency (%)
                                                                                                                                    100
                               0.1
       VOUT Deviation (%)
                              0.05                                                                                                   75
                                 0
                                                                                                                                     50
                              -0.05
                               -0.1        VIN = 12 V
                                           VIN = 24 V                                                                                25
                              -0.15        VIN = 36 V
                                           VIN = 48 V
                               -0.2                                                                                                   0
                                 0.001             0.01          0.1          1          3                                                0     0.1    0.2     0.3      0.4       0.5   0.6       0.7
                                                          IOUT (A)                                                                                                   VFB (V)                            D005
                                                                                         D005
5.5 0.754
5 0.752
                    4.5                                                                                  0.75
      VOUT (V)
                                                                                            VFB (V)
                     4                                                                                  0.748
                                                                           3A
                                                                           2A
                    3.5                                                    1A                           0.746
                                                                           0.5 A
                                                                           0.1 A
                     3                                                                                  0.744
                      4.5          5              5.5            6              6.5                         -50     -25   0       25     50     75      100   125    150
                                                VIN (V)                             D007
                                                                                                                              Junction Temperature (qC)                D010
                    5.2
                                                                                             UVLO (V)                                                         UVLO_L
                     5                                                                                   3.8
                    4.8                                                                                 3.75
                    4.6
                                                                                                         3.7
                    4.4
                    4.2                                                                                 3.65
                     4                                                                                   3.6
                     -50     -25   0       25     50     75      100    125     150                        -50     -25    0       25     50     75     100    125    150
                                       Junction Temperature (°C)                    D011
                                                                                                                              Junction Temperature (qC)                D009
IOUT = 0 A
    Figure 7-9. High-Side Current Limit vs Junction                                                               Figure 7-10. UVLO Threshold
                     Temperature
8 Detailed Description
8.1 Overview
The LV14360 regulator is an easy-to-use step-down DC-DC converter that operates from a 4.3-V to 60-V supply
voltage. The device integrates a 155-mΩ (typical) high-side MOSFET and is capable of delivering up to 3-A DC
load current with exceptional efficiency and thermal performance in a very small solution size. The operating
current is typically 300 μA under no load condition (not switching). When the device is disabled, the supply
current is typically 1 μA. An extended family is available in 1-A and 2-A load options in pin-to-pin compatible
packages.
The LV14360 implements constant frequency peak current mode control with sleep mode at light load to achieve
high efficiency. The device is internally compensated, which reduces design time, and requires fewer external
components. The switching frequency is programmable from 200 kHz to 2 MHz by an external resistor RT. The
LV14360 is also capable of synchronization to an external clock within the 250-kHz to 2 MHz frequency range,
which allows the device to be optimized to fit small board space at higher frequency, or high efficient power
conversion at lower frequency.
Other features are included for more comprehensive system requirements, including precision enable,
adjustable soft-start time, and approximate 90% duty cycle by BOOT capacitor recharge circuit. These features
provide a flexible and easy-to-use platform for a wide range of applications. Protection features include over
temperature shutdown, VOUT overvoltage protection (OVP), VIN undervoltage lockout (UVLO), cycle-by-cycle
current limit, and short-circuit protection with frequency foldback.
                                                                          VSW
                                                                                              D = tON/ TSW
                                                                     VIN
                                                  SW Voltage
                                                                                      tON         tOFF
                                                                                                                         t
                                                                      0
                                                                     -VD
                                                                                        TSW
                                                                            iL
ILPK
                                                  Inductor Current
                                                                     IOUT
                                                                                                                  ûiL
                                                                                                                         t
                                                                      0
Figure 8-1. SW Node and Inductor Current Waveforms in Continuous Conduction Mode (CCM)
The LV14360 employs fixed frequency peak current mode control. A voltage feedback loop is used to get
accurate DC voltage regulation by adjusting the peak current command based on voltage offset. The peak
inductor current is sensed from the high-side switch and compared to the peak current to control the ON time
of the high-side switch. The voltage feedback loop is internally compensated, which allows for fewer external
components, makes it easy to design, and provides stable operation with almost any combination of output
capacitors. The regulator operates with fixed switching frequency at normal load condition. At very light load, the
LV14360 operates in sleep mode to maintain high efficiency and switching frequency will decrease with reduced
load current.
8.3.2 Slope Compensation
The LV14360 adds a compensating ramp to the MOSFET switch current sense signal. This slope compensation
prevents subharmonic oscillations at duty cycles greater than 50%. The peak current limit of the high-side switch
is not affected by the slope compensation and remains constant over the full duty cycle range.
8.3.3 Sleep Mode
The LV14360 operates in sleep mode at light load currents to improve efficiency by reducing switching and
gate-drive losses. If the output voltage is within regulation and the peak switch current at the end of any
switching cycle is below the current threshold of 300 mA, the device enters sleep mode. The sleep-mode current
threshold is the peak switch current level corresponding to a nominal internal COMP voltage of 400 mV.
When in sleep mode, the internal COMP voltage is clamped at 400 mV and the high-side MOSFET is inhibited,
and the device draws only 300 μA (typical) input quiescent current. Since the device is not switching, the output
voltage begins to decay. The voltage control loop responds to the falling output voltage by increasing the internal
COMP voltage. The high-side MOSFET is enabled and switching resumes when the error amplifier lifts internal
COMP voltage above 400 mV. The output voltage recovers to the regulated value, and internal COMP voltage
eventually falls below the sleep-mode threshold at which time the device again enters sleep mode.
8.3.4 Low Dropout Operation and Bootstrap Voltage (BOOT)
The LV14360 provides an integrated bootstrap voltage regulator. A small capacitor between the BOOT and
SW pins provides the gate drive voltage for the high-side MOSFET. The BOOT capacitor is refreshed when
the high-side MOSFET is off and the external low-side diode conducts. The recommended value of the BOOT
capacitor is 0.1 μF. TI recommends a ceramic capacitor with an X7R or X5R grade dielectric with a voltage rating
of 16 V or greater for stable performance over temperature and voltage.
When operating with a low voltage difference from input to output, the high-side MOSFET of the LV14360
operates at approximate 90% duty cycle. When the high-side MOSFET is continuously on for five or six
switching cycles (five or six switching cycles for frequency lower than 1 MHz, and 10 or 11 switching cycles
for frequency higher than 1 MHz) and the voltage from BOOT to SW drops below 3.2 V, the high-side MOSFET
is turned off and an integrated low-side MOSFET pulls SW low to recharge the BOOT capacitor.
Since the gate drive current sourced from the BOOT capacitor is small, the high-side MOSFET can remain on for
many switching cycles before the MOSFET is turned off to refresh the capacitor. Thus the effective duty cycle of
the switching regulator can be high, approaching 90%. The effective duty cycle of the converter during dropout
is mainly influenced by the voltage drops across the power MOSFET, the inductor resistance, the low-side diode
voltage, and the printed circuit board resistance.
8.3.5 Adjustable Output Voltage
The internal voltage reference produces a precise 0.75 V (typical) voltage reference over the operating
temperature range. The output voltage is set by a resistor divider from output voltage to the FB pin. It is
recommended to use 1% tolerance or better and temperature coefficient of 100 ppm or less divider resistors.
Select the low side resistor RFBB for the desired divider current and use Equation 1 to calculate high-side RFBT.
Larger value divider resistors are good for efficiency at light load. However, if the values are too high, the
regulator will be more susceptible to noise and voltage errors from the FB input current may become noticeable.
RFBB in the range from 10 kΩ to 100 kΩ is recommended for most applications.
                                                                          VOUT
RFBT
FB
RFBB
             VOUT 0.75
     RFBT              u RFBB
                0.75                                                                                                        (1)
                                                      IEN_HYS     IEN
                                                                            VIN
                                                                                   VIN
RENT
                                                                            EN
                                                           VEN                    RENB
                 VSTART VSTOP
      RENT
                      IHYS                                                                                                                      (2)
                       VEN
      RENB
                 VSTART VEN
                                      IEN
                    RENT                                                                                                                        (3)
where
•    VSTART is the desired voltage threshold to enable LV14360
•    VSTOP is the desired voltage threshold to disable device
•    IEN = 1 μA
•    IHYS = 3.6 μA, typically
8.3.7 External Soft Start
The LV14360S has an external soft-start pin for programmable output ramp up time. The soft-start feature is
used to prevent inrush current impacting the LV14360 and its load when power is first applied. The soft-start
time can be programed by connecting an external capacitor CSS from SS pin to GND. An internal current source
(typically I SS = 3 μA) charges CSS and generates a ramp from 0 V to VREF. The soft-start time can be calculated
by Equation 4:
The internal soft start resets while device is disabled or in thermal shutdown.
8.3.8 Switching Frequency and Synchronization (RT/SYNC)
The switching frequency of the LV14360 can be programmed by the resistor RT from the RT/SYNC pin and GND
pin. The RT/SYNC pin cannot be left floating or shorted to ground. To determine the timing resistance for a given
switching frequency, use Equation 5 or the curve in Figure 8-4. Table 8-1 gives typical RT values for a given ƒSW.
                                                      1.088
      RT (k:)      42904 u ¦SW N+]                                                                                                              (5)
                                                      140
120
100
                                                       80
                                            RT (k:)
60
40
20
                                                        0
                                                            0          500         1000         1500         2000
                                                                              Frequency (kHz)                  D008
The LV14360 switching action can also be synchronized to an external clock from 250 kHz to 2 MHz. Connect
a square wave to the RT/SYNC pin through either circuit network shown in Figure 8-5. Internal oscillator is
synchronized by the falling edge of external clock. The recommendations for the external clock include: high
level no lower than 1.7 V, low level no higher than 0.5 V, and have a pulse width greater than 30 ns. When using
a low impedance signal source, the frequency setting resistor RT is connected in parallel with an AC coupling
capacitor CCOUP to a termination resistor RTERM (for example, 50 Ω). The two resistors in series provide the
default frequency setting resistance when the signal source is turned off. A 10-pF ceramic capacitor can be used
for CCOUP. Figure 8-6, Figure 8-7, and Figure 8-8 show the device synchronized to an external system clock.
                          CCOUP
                                              PLL                                                              PLL
                             RT
         Lo-Z                          RT/SYNC                        Hi-Z                            RT/SYNC
         Clock                                                        Clock
        Source          RTERM                                        Source           RT
Equation 6 calculates the maximum switching frequency limitation set by the minimum controllable on time and
the input to output step down ratio. Setting the switching frequency above this value will cause the regulator to
skip switching pulses to achieve the low duty cycle required at maximum input voltage.
where
•    IOUT = Output current
•    RIND = Inductor series resistance
•    VIN_MAX = Maximum input voltage
•    VOUT = Output voltage
•    VD = Diode voltage drop
•    RDS_ON = High-side MOSFET switch on resistance
•    tON = Minimum on-time
8.3.9 Power Good (PGOOD)
The LV14360P has a built-in power-good flag shown on the PGOOD pin to indicate whether the output voltage
is within its regulation level. The PGOOD signal can be used for start-up sequencing of multiple rails or fault
protection. The PGOOD pin is an open-drain output that requires a pullup resistor to an appropriate DC voltage.
Voltage seen by the PGOOD pin must never exceed 7 V. A resistor divider pair can be used to divide the voltage
down from a higher potential. A typical range of pullup resistor value is 10 kΩ to 100 kΩ.
Refer to Figure 8-9. When the FB voltage is within the power-good band, +7% above and –6% below the internal
reference VREF typically, the PGOOD switch is turned off, and the PGOOD voltage is pulled up to the voltage
level defined by the pullup resistor or divider. When the FB voltage is outside of the tolerance band, +9% above
or –8% below VREF typically, the PGOOD switch is turned on, and the PGOOD pin voltage is pulled low to
indicate power bad.
                                                   VREF
                                                  109%
                                                  107%
                                                  94%
                                                  92%
PGOOD
High
Low
Lower frequency also means lower switching loss. Frequency foldback reduces power dissipation and prevents
overheating and potential damage to the device.
8.3.11 Overvoltage Protection
The LV14360 employs an output overvoltage protection (OVP) circuit to minimize voltage overshoot when
recovering from output fault conditions or strong unload transients in designs with low output capacitance.
The OVP feature minimizes output overshoot by turning off the high-side switch immediately when FB voltage
reaches to the rising OVP threshold, which is nominally 109% of the internal voltage reference VREF. When the
FB voltage drops below the falling OVP threshold which is nominally 107% of VREF, the high-side MOSFET
resumes normal operation.
8.3.12 Thermal Shutdown
The LV14360 provides an internal thermal shutdown to protect the device when the junction temperature
exceeds 170°C (typical). The high-side MOSFET stops switching when thermal shutdown activates. Once the
die temperature falls below 158°C (typical), the device reinitiates the power-up sequence controlled by the
internal soft-start circuitry.
8.4 Device Functional Modes
8.4.1 Shutdown Mode
The EN pin provides electrical ON and OFF control for the LV14360. When VEN is below 1 V, the device is in
shutdown mode. The switching regulator is turned off and the quiescent current drops to 1 µA, typically. The
LV14360 also employs UVLO protection. If VIN voltage is below the UVLO level, the regulator is turned off.
8.4.2 Active Mode
The LV14360 is in active mode when VEN is above the precision enable threshold and VIN is above its UVLO
level. The simplest way to enable the LV14360 is to connect the EN pin to VIN pin. This allows self start-up when
the input voltage is in the operation range: 4.3 V to 60 V. See Section 8.3.6 for details on setting these operating
levels.
In active mode, depending on the load current, the LV14360 is in one of three modes:
1. Continuous conduction mode (CCM) with fixed switching frequency when load current is above half of the
   peak-to-peak inductor current ripple
2. Discontinuous conduction mode (DCM) with fixed switching frequency when load current is lower than half of
   the peak-to-peak inductor current ripple in CCM operation
3. Sleep-mode when internal COMP voltage drop to 400 mV at very light load
8.4.3 CCM Mode
CCM operation is employed in the LV14360 when the load current is higher than half of the peak-to-peak
inductor current. In CCM operation, the frequency of operation is fixed, output voltage ripple will be at a minimum
in this mode and the maximum output current of 3 A can be supplied by the LV14360.
8.4.4 Light Load Operation
When the load current is lower than half of the peak-to-peak inductor current in CCM, the LV14360 operates in
DCM. At even lighter current loads, sleep mode is activated to maintain high efficiency operation by reducing
switching and gate-drive losses.
                                                                                          L        5V/3A
                                                             EN         SW
                                                                                          COUT
                                                                                 D
                                                                                                     RFBT
RT/SYNC FB
                                                                                                     RFBB
                                           RT                 SS        GND
CSS
               VOUT 0.75
     RFBT                u RFBB
                  0.75                                                                                                (7)
Choose the value of RFBT to be 100 kΩ. With the desired output voltage set to 5 V and the VFB = 0.75 V, the
RFBB value can then be calculated using Equation 7. The formula yields to a value 17.65 kΩ. Choose the closest
available value of 17.8 kΩ for RFBB.
9.2.2.2 Switching Frequency
For desired frequency, use Equation 8 to calculate the required value for RT.
                                      1.088
     RT (k:)    42904 u ¦SW N+]                                                                                       (8)
For 500 KHz, the calculated RT is 49.66 kΩ, and standard value 49.9 kΩ can be used to set the switching
frequency at 500 KHz.
9.2.2.3 Output Inductor Selection
The most critical parameters for the inductor are the inductance, saturation current, and the RMS current. The
inductance is based on the desired peak-to-peak ripple current ΔiL. Since the ripple current increases with
the input voltage, the maximum input voltage is always used to calculate the minimum inductance LMIN. Use
Equation 9 to calculate the minimum value of the output inductor. KIND is a coefficient that represents the amount
of inductor ripple current relative to the maximum output current. A reasonable value of KIND should be 20% to
40%. During an instantaneous short or overcurrent operation event, the RMS and peak inductor current can be
high. The inductor current rating should be higher than current limit.
In general, it is preferable to choose lower inductance in switching power supplies, because it usually
corresponds to faster transient response, smaller DCR, and reduced size for more compact designs. But too
low of an inductance can generate too large of an inductor current ripple such that overcurrent protection at the
full load can be falsely triggered. It also generates more conduction loss since the RMS current is slightly higher.
Larger inductor current ripple also implies larger output voltage ripple with same output capacitors. With peak
current mode control, it is not recommended to have too small of an inductor current ripple. A larger peak current
ripple improves the comparator signal-to-noise ratio.
For this design example, choose KIND = 0.4. The minimum inductor value is calculated to be 7.64 µH, and a
nearest standard value is chosen: 8.2 µH. A standard 8.2-μH ferrite inductor with a capability of 3-A RMS current
and 6-A saturation current can be used.
9.2.2.4 Output Capacitor Selection
Choose the output capacitor or capacitors, COUT, with care since it directly affects the steady state output
voltage ripple, loop stability, and the voltage overshoot and undershoot during load current transients.
The output ripple is essentially composed of two parts. One is caused by the inductor current ripple going
through the equivalent series resistance (ESR) of the output capacitors:
The other is caused by the inductor current ripple charging and discharging the output capacitors:
The two components in the voltage ripple are not in-phase, so the actual peak-to-peak ripple is smaller than the
sum of two peaks.
Output capacitance is usually limited by transient performance specifications if the system requires tight voltage
regulation with presence of large current steps and fast slew rate. When a fast large load increase happens,
output capacitors provide the required charge before the inductor current can slew up to the appropriate level.
The control loop of the regulator usually needs three or more clock cycles to respond to the output voltage
droop. The output capacitance must be large enough to supply the current difference for three clock cycles
to maintain the output voltage within the specified range. Equation 13 shows the minimum output capacitance
needed for specified output undershoot. When a sudden large load decrease happens, the output capacitors
absorb energy stored in the inductor. The catch diode cannot sink current so the energy stored in the inductor
results in an output voltage overshoot. Equation 14 calculates the minimum capacitance required to keep the
voltage overshoot within a specified range.
                 3 u (IOH IOL )
      COUT !
                  ¦SW u 9US                                                                                                  (13)
                           2   2
                          IOH IOL
      COUT !                                      uL
                 (VOUT      VOS )2      2
                                       VOUT                                                                                  (14)
where
•    KIND = Ripple ratio of the inductor ripple current (ΔiL / IOUT)
•    IOL = Low level output current during load transient
•    IOH = High level output current during load transient
•    VUS = Target output voltage undershoot
•    VOS = Target output voltage overshoot
For this design example, the target output ripple is 50 mV. Presuppose ΔVOUT_ESR = ΔVOUT_C = 50 mV, and
choose KIND = 0.4. Equation 11 yields ESR no larger than 41.7 mΩ and Equation 12 yields COUT no smaller than
6 μF. For the target overshoot and undershoot range of this design, VUS = VOS = 5% × VOUT = 250 mV. COUT
can be calculated to be no smaller than 64.8 μF and 6.4 μF by Equation 13 and Equation 14, respectively. In
summary, the most stringent criteria for the output capacitor is 100 μF. For this design example, two 47-μF, 16-V,
X7R ceramic capacitors with 5-mΩ ESR are used in parallel.
9.2.2.5 Schottky Diode Selection
The breakdown voltage rating of the diode is preferred to be 25% higher than the maximum input voltage.
The current rating for the diode should be equal to the maximum output current for best reliability in most
applications. In cases where the input voltage is much greater than the output voltage, the average diode current
is lower. In this case, it is possible to use a diode with a lower average current rating, approximately (1 – D) ×
IOUT, however, the peak current rating should be higher than the maximum load current. A 3-A rated diode is a
good starting point.
9.2.2.6 Input Capacitor Selection
The LV14360 device requires high frequency input decoupling capacitor or capacitors and a bulk input capacitor,
depending on the application. The typical recommended value for the high frequency decoupling capacitor is 4.7
μF to 10 μF. A high-quality ceramic capacitor type X5R or X7R with sufficient voltage rating is recommended.
To compensate the derating of ceramic capacitors, a voltage rating of twice the maximum input voltage is
recommended. Additionally, some bulk capacitance can be required, especially if the LV14360 circuit is not
located within approximately 5 cm from the input voltage source. This capacitor is used to provide damping to
the voltage spike due to the lead inductance of the cable or the trace. For this design, two 2.2-μF, X7R ceramic
capacitors rated for 100 V are used. Use a 0.1-μF capacitor for high-frequency filtering and place it as close as
possible to the device pins.
9.2.2.7 Bootstrap Capacitor Selection
Every LV14360 design requires a bootstrap capacitor (CBOOT). The recommended capacitor is 0.1 μF and rated
16 V or higher. The bootstrap capacitor is located between the SW pin and the BOOT pin. The bootstrap
capacitor must be a high-quality ceramic type with an X7R or X5R grade dielectric for temperature stability.
Unless otherwise specified the following conditions apply: VIN = 24 V, fSW = 500 KHz, L = 8.2 µH, COUT = 2 × 47 µF, TA =
25°C.
                                                                                        VOUT = 5 V                 IOUT = 2 A
                  VOUT = 5 V                      IOUT = 2 A
                                                                                         Figure 9-3. Start-up By VIN
                    Figure 9-2. Start-up by EN
VOUT = 5 V VOUT = 5 V
                                                  Output Bypass
                                                  Capacitor
                                                                                       Output
                                                                                       Inductor
                                                                             Rectifier Diode
                                     BOOT
                                     Capacitor
                    Input Bypass
                    Capacitor
                                                   BOOT                       SW
                                                                                                 Soft-Start
                                                                                                 Capacitor
                                                   VIN                       GND
EN SS
www.ti.com 18-May-2023
PACKAGING INFORMATION
           Orderable Device             Status    Package Type Package Pins Package             Eco Plan            Lead finish/           MSL Peak Temp          Op Temp (°C)                Device Marking       Samples
                                          (1)                  Drawing        Qty                   (2)             Ball material                  (3)                                             (4/5)
                                                                                                                         (6)
LV14360PDDAR ACTIVE SO PowerPAD DDA 8 2500 RoHS & Green NIPDAU | NIPDAUAG Level-2-260C-1 YEAR -40 to 150 14360P Samples
LV14360SDDAR ACTIVE SO PowerPAD DDA 8 2500 RoHS & Green NIPDAU | NIPDAUAG Level-2-260C-1 YEAR -40 to 150 14360S Samples
(1)
  The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
   RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3)
      MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
      There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5)
   Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
   Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two
lines if the finish value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
                                                                                                Addendum-Page 1
                               PACKAGE OPTION ADDENDUM
www.ti.com 18-May-2023
             Addendum-Page 2
                                                                              PACKAGE MATERIALS INFORMATION
www.ti.com 12-Jan-2024
                                                                                                                    B0 W
                                       Reel
                                     Diameter
                                                                                  Cavity           A0
                                                              A0   Dimension designed to accommodate the component width
                                                              B0   Dimension designed to accommodate the component length
                                                              K0   Dimension designed to accommodate the component thickness
                                                              W    Overall width of the carrier tape
                                                              P1   Pitch between successive cavity centers
Sprocket Holes
Q1 Q2 Q1 Q2
Pocket Quadrants
                                                                    Pack Materials-Page 1
                                                                PACKAGE MATERIALS INFORMATION
www.ti.com 12-Jan-2024
                                                               Width (mm)
                                                                              H
                      W
                                                        Pack Materials-Page 2
                                                                                                            PACKAGE OUTLINE
DDA0008B                                                    SCALE 2.400
                                                                                   PowerPAD TM SOIC - 1.7 mm max height
                                                                                                                        PLASTIC SMALL OUTLINE
                                                                                                                                  C
                                        6.2
                                            TYP                                                            SEATING PLANE
                                        5.8
               A
                                                 PIN 1 ID
                                                 AREA                                                                         0.1 C
                                                                                        6X 1.27
                                                                              8
                     1
            5.0                                                                       2X
            4.8                                                                      3.81
           NOTE 3
                     4
                                                                          5
                                                                                        0.51
                                                                                   8X
                                         4.0                                            0.31
                         B                                                                                                      1.7 MAX
                                         3.8                                             0.25     C A B
                                        NOTE 4
                                                                                    0.25
                                                                                         TYP
                                                                                    0.10
SEE DETAIL A
                     4                                                        5
                                                                                  EXPOSED
                                                                                  THERMAL PAD
               3.4                                                                                     0.25
                                           9                                                    GAGE PLANE
               2.8
                                                                                                                                            0.15
                                                                                                    0 -8               1.27                 0.00
                     1                                                        8
                                                                                                                       0.40
                                                                                                                              DETAIL A
                                          2.71                                                                                  TYPICAL
                                          2.11
                                                                                                                                 4214849/A 08/2016
                                                                                                       PowerPAD is a trademark of Texas Instruments.
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
   per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not
   exceed 0.15 mm per side.
4. This dimension does not include interlead flash. Interlead flash shall not exceed 0.25 mm per side.
5. Reference JEDEC registration MS-012.
                                                                              www.ti.com
                                                                                  EXAMPLE BOARD LAYOUT
DDA0008B                                                                 PowerPAD TM SOIC - 1.7 mm max height
                                                                                                              PLASTIC SMALL OUTLINE
                                                            (2.95)
                                                           NOTE 9
                                                            (2.71)                SOLDER MASK
                                                                                  DEFINED PAD
                                                         SOLDER MASK
                                                           OPENING
                     8X (1.55)                                                                SEE DETAILS
                                   1
                                                                                          8
8X (0.6)
                                                                                                          (3.4)
                        SYMM                                9                                         SOLDER MASK
                                                                                              (1.3)
                                                                                              TYP       OPENING
                                                                                                                    (4.9)
                                                                                                                   NOTE 9
                     6X (1.27)
                                   4                                                      5
                (R0.05) TYP
                                                            SYMM                         METAL COVERED
                     ( 0.2) TYP                                                          BY SOLDER MASK
                             VIA
                                             (1.3) TYP
                                                             (5.4)
4214849/A 08/2016
NOTES: (continued)
                                                                     www.ti.com
                                                                                   EXAMPLE STENCIL DESIGN
DDA0008B                                                                  PowerPAD TM SOIC - 1.7 mm max height
                                                                                                            PLASTIC SMALL OUTLINE
                                                              (2.71)
                                                            BASED ON
                                                           0.125 THICK
                                                             STENCIL
                        8X (1.55)                                                               (R0.05) TYP
                                    1
                                                                                          8
8X (0.6)
                                                                                                  (3.4)
                     SYMM                                     9                                BASED ON
                                                                                              0.125 THICK
                                                                                                STENCIL
6X (1.27)
                                                                                          5
                                    4
              METAL COVERED
                                                              SYMM                        SEE TABLE FOR
              BY SOLDER MASK
                                                                                          DIFFERENT OPENINGS
                                                                                          FOR OTHER STENCIL
                                                              (5.4)
                                                                                          THICKNESSES
4214849/A 08/2016
NOTES: (continued)
11. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
    design recommendations.
12. Board assembly site may have different recommendations for stencil design.
                                                                      www.ti.com
                                       IMPORTANT NOTICE AND DISCLAIMER
TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATA SHEETS), DESIGN RESOURCES (INCLUDING REFERENCE
DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS”
AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD
PARTY INTELLECTUAL PROPERTY RIGHTS.
These resources are intended for skilled developers designing with TI products. You are solely responsible for (1) selecting the appropriate
TI products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable
standards, and any other safety, security, regulatory or other requirements.
These resources are subject to change without notice. TI grants you permission to use these resources only for development of an
application that uses the TI products described in the resource. Other reproduction and display of these resources is prohibited. No license
is granted to any other TI intellectual property right or to any third party intellectual property right. TI disclaims responsibility for, and you
will fully indemnify TI and its representatives against, any claims, damages, costs, losses, and liabilities arising out of your use of these
resources.
TI’s products are provided subject to TI’s Terms of Sale or other applicable terms available either on ti.com or provided in conjunction with
such TI products. TI’s provision of these resources does not expand or otherwise alter TI’s applicable warranties or warranty disclaimers for
TI products.
TI objects to and rejects any additional or different terms you may have proposed. IMPORTANT NOTICE
                             Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
                                            Copyright © 2024, Texas Instruments Incorporated