application UCC1807-1/-2/-3

INFO UCC2807-1/-2/-3
available
UCC3807-1/-2/-3
Programmable Maximum Duty Cycle PWM Controller
FEATURES DESCRIPTION
User Programmable Maximum PWM The UCC3807 family of high speed, low power integrated circuits contains
Duty Cycle all of the control and drive circuitry required for off-line and DC-to-DC fixed
frequency current mode switching power supplies with minimal external
100m A Startup Current
parts count.
Operation to 1MHz
These devices are similar to the UCC3800 family, but with the added fea-
Internal Full Cycle Soft Start ture of a user programmable maximum duty cycle. Oscillator frequency and
maximum duty cycle are programmed with two resistors and a capacitor.
Internal Leading Edge Blanking of The UCC3807 family also features internal full cycle soft start and internal
Current Sense Signal
leading edge blanking of the current sense input.
1A Totem Pole Output The UCC3807 family offers a variety of package options, temperature
range options, and choice of critical voltage levels. The family has UVLO
thresholds and hysteresis levels for off-line and battery powered systems.
Thresholds are shown in the table below.

Part Number Turn-on Threshold Turn-off Threshold Packages

UCCx807-1 7.2V 6.9V J
UCCx807-2 12.5V 8.3V N, D
UCCx807-3 4.3V 4.1V N, D, PW

BLOCK DIAGRAM

UDG-95001-1

SLUS163 - JUNE 1997 1

 UCC1807-1/-2/-3
UCC2807-1/-2/-3
UCC3807-1/-2/-3

ABSOLUTE MAXIMUM RATINGS CONNECTION DIAGRAMS

Supply Voltage (IDD 10mA). . . . . . . . . . . . . . . . . . . . . . . 13.5V
Supply Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30mA DIL-8, SOIC-8, TSSOP-8 (Top View)
OUT Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±1A J, N, D or PW Packages
Analog Inputs (FB, CS) . . . . . . . . . . . . . –0.3V to (VDD + 0.3V)
Power Dissipation at TA +25°C (N or J packages) . . . . . . . . 1W
Power Dissipation at TA +25°C (D package) . . . . . . . . . . 0.65W
Storage Temperature . . . . . . . . . . . . . . . . . . . –65°C to +150°C
Junction Temperature . . . . . . . . . . . . . . . . . . . –65°C to +150°C
Lead Temperature (Soldering, 10 sec.) . . . . . . . . . . . . . +300°C
All currents are positive into, negative out of the specified ter-
minal. Consult Packaging Section of Databook for thermal limi-
tations and considerations of packages.

ORDERING INFORMATION
UCC 807 –

UVLO Threshold
Package
Temperature Range

ELECTRICAL CHARACTERISTICS:Unless otherwise stated these specifications apply for TA = –55°C to +125°C for
UCC1807-1/-2/-3; –40°C to +85°C for UCC2807-1/-2/-3; and 0°C to +70°C for UCC3807-1/-2/-3; VDD = 10V (Note 6), RA = 12kW ,
RB = 4.7kW , CT = 330pF, 1.0m F capacitor from VDD to GND, TA = TJ.
PARAMETER TEST CONDITIONS MIN TYP MAX UNITS
Oscillator Section Section
Frequency 175 202 228 kHz
Temperature Stability (Note 5) 2.5 %
Amplitude (Note 1) 1/3VDD V
Error Amplifier Section
Input Voltage COMP = 2.0V 1.95 2.00 2.05 V
Input Bias Current –1 1 m A
Open Loop Voltage Gain 60 80 dB
COMP Sink Current FB = 2.2V, COMP = 1.0V 0.3 2.5 mA
COMP Source Current FB = 1.3V, COMP = 4.0V –0.2 –0.5 mA
PWM Section
Maximum Duty Cycle 75 78 81 %
Minimum Duty Cycle COMP = 0V 0 %
Current Sense Section
Gain (Note 2) 1.1 1.65 1.8 V/V
Maximum Input Signal COMP = 5.0V (Note 3) 0.9 1.0 1.1 V
Input Bias Current –200 200 nA
CS Blank Time 50 100 150 ns
Overcurrent Threshold 1.4 1.5 1.6 V
COMP to CS Offset CS = 0V 0.55 1.1 1.65 V
Output Section
OUT Low Level I = 100mA 0.4 1 V
OUT High Level I = –100mA, VDD - OUT 0.4 1 V
Rise/Fall Time CL = 1nF (Note 5) 20 100 ns
Undervoltage Lockout Section
2
 UCC1807-1/-2/-3
UCC2807-1/-2/-3
UCC3807-1/-2/-3
ELECTRICAL CHARACTERISTICS:Unless otherwise stated these specifications apply for TA = –55°C to +125°C for
UCC1807-1/-2/-3; –40°C to +85°C for UCC2807-1/-2/-3; and 0°C to +70°C for UCC3807-1/-2/-3; VDD = 10V (Note 6), RA = 12kW ,
RB = 4.7kW , CT = 330pF, 1.0m F capacitor from VDD to GND, TA = TJ.
PARAMETER TEST CONDITIONS MIN TYP MAX UNITS
Start Threshold UCCx807-1 (Note 4) 6.6 7.2 7.8 V
UCCx807-2 11.5 12.5 13.5 V
UCCx807-3 4.1 4.3 4.5 V
Minimum Operating Voltage After Start UCCx807-1 (Note 4) 6.3 6.9 7.5 V
UCCx807-2 7.6 8.3 9.0 V
UCCx807-3 3.9 4.1 4.3 V
Hysteresis UCCx807-1 0.1 0.3 0.5 V
UCCx807-2 3.5 4.2 5.1 V
UCCx807-3 0.1 0.2 0.3 V
Soft Start Section
COMP Rise Time FB = 1.8V, From 0.5V to 4.0V 4 ms
Overall Section
Startup Current VDD < Start Threshold (UCCx807-1,-3) 0.1 0.2 mA
VDD < Start Threshold (UCCx807-2) 0.15 0.25 mA
Operating Supply Current FB = 0V, CS = 0V, No Load (Note 7) 1.3 2.1 mA
VDD Zener Shunt Voltage IDD = 10mA 12.0 13.5 15.0 V
Shunt to Start Difference 0.5 1.0 V
Note 1: Measured at TRIG; signal minimum = 1/3 VDD, maximum = 2/3 VDD.
VCOMP
Note 2: Gain is defined by: A , 0 VCS 0.8V
VCS
Note 3: Parameter measured at trip point of latch with FB at 0V.
Note 4: Start Threshold and Zener Shunt thresholds track one another.
Note 5: Ensured by design. Not 100% tested in production.
Note 6: Adjust VDD above the start threshold before setting at 10V for UCC3807-2.
Note 7: Does not include current in external timing RC network.

PIN DESCRIPTIONS
COMP: COMP is the output of the error amplifier and the affected by the leading edge blanking and the CS to
input of the PWM comparator. The error amplifier in the OUT propagation delay.
UCC3807 is a low output impedance, 2MHz operational The overcurrent comparator is only intended for fault
amplifier. COMP can both source and sink current. The sensing. Exceeding the overcurrent threshold causes a
error amplifier is internally current limited, which allows soft start cycle.
zero duty cycle by externally forcing COMP to GND.
FB: The inverting input to the error amplifier. For best
The UCC3807 family features built-in full cycle soft start. stability, keep connections to FB as short as possible and
Soft start is implemented as a clamp on the maximum stray capacitance as small as possible.
COMP voltage.
GND: Reference ground and power ground for all func-
CS: Current sense input. There are two current sense tions of the part.
comparators on the chip, the PWM comparator and an
overcurrent comparator. OUT: The output of a high current power driver capable
of driving the gate of a power MOSFET with peak cur-
The UCC3807 also contains a leading edge blanking cir- rents exceeding 1A. OUT is actively held low when VDD
cuit, which disconnects the external CS signal from the is below the UVLO threshold.
current sense comparator during the 100ns interval im-
mediately following the rising edge of the signal at the The high current power driver consists of MOSFET out-
OUT pin. In most applications, no analog filtering is re- put devices in a totem pole configuration. This allows the
quired on CS. Compared to an external RC filtering tech- output to switch from VDD to GND. The output stage
nique, leading edge blanking provides a smaller effective also provides a very low impedance which minimizes
CS to OUT propagation delay. Note, however, that the overshoot and undershoot. In most cases, external
minimum non-zero on-time of the OUT signal is directly Schottky clamp diodes are not required.
3
 UCC1807-1/-2/-3
UCC2807-1/-2/-3
UCC3807-1/-2/-3
PIN DESCRIPTIONS (cont.)
TRIG/DISCH: Oscillator control pins. Trig is the oscillator For best performance, keep the lead from CT to GND as
timing input, which has an RC-type charge/discharge sig- short as possible. A separate ground connection for CT is
nal controlling the chip’s internal oscillator. DISCH is the desirable. The minimum value of RA is 10kW , the mini-
pin which provides the low impedance discharge path for mum value of RB is 2.2kW , and the minimum value of CT
the external RC network during normal operation. Oscil- is 47pF.
lator frequency and maximum duty cycle are computed
VDD: The power input connection for this device. Total
as follows:
VDD current is the sum of quiescent current and the av-
1.4 erage OUT current. Knowing the operating frequency
fre que ncy
RA 2 R B CT and the MOSFET gate charge (Qg), average OUT cur-
RA RB rent can be calculated from
duty cycle
R A 2R B IOUT = Qg F, where F is frequency.
as shown in Figure 1. To prevent noise problems, bypass VDD to GND with a
ceramic capacitor as close to the chip as possible in par-
allel with an electrolytic capacitor.

UDG-95002-1

Figure 1. Oscillator Block Diagram

APPLICATIONS INFORMATION
The circuit shown in Fig. 2 illustrates the use of the
T1:
UCC3807 in a typical off-line application. The 100W,
Core Magnetics Inc. #P-42625-UG (ungapped)
200kHz, universal input forward converter produces a Primary: 28 turns of 2x #26AWG
regulated 12VDC at 8 Amps. The programmable maxi- Secondary: 6 turns of 50x0.2mm Litz wire
mum duty cycle of the UCC3807 allows operation down L1:
to 80VRMS and up to 265VRMS with a simple RCD Core: Magnetics Inc. #P-42625-SG-37 (0.020”
clamp to limit the MOSFET voltage and provide core re- gap)
set. In this application the maximum duty cycle is set to Main Winding: 13 turns of 2x #18AWG
about 65%. Another feature of the design is the use of a Second Winding: 11 turns of #26AWG
flyback winding on the output filter choke for both boot- Magnetics Inc.
900 E. Butler Road
strapping and voltage regulation. This method of loop clo-
P.O. Box 391
sure eliminates the optocoupler and secondary side Butler, PA 16003
regulator, common to most off-line designs, while provid- Tel: (412) 282-8282
ing good line and load regulation. Fax: (412) 282-6955
4
 UCC1807-1/-2/-3
UCC2807-1/-2/-3
UCC3807-1/-2/-3
APPLICATIONS INFORMATION (cont.)

UDG-96174

Figure 2. Typical Off-line Application Using UCC3807-2

5
 PACKAGE OPTION ADDENDUM
www.ti.com 4-Nov-2005

PACKAGING INFORMATION

Orderable Device Status (1) Package Package Pins Package Eco Plan (2) Lead/Ball Finish MSL Peak Temp (3)
Type Drawing Qty
UCC2807D-1 ACTIVE SOIC D 8 75 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC2807D-2 ACTIVE SOIC D 8 75 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC2807D-3 ACTIVE SOIC D 8 75 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC2807DTR-1 ACTIVE SOIC D 8 2500 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC2807DTR-1G4 ACTIVE SOIC D 8 2500 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC2807DTR-2 ACTIVE SOIC D 8 2500 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC2807DTR-2G4 ACTIVE SOIC D 8 2500 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC2807DTR-3 ACTIVE SOIC D 8 2500 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC2807DTR-3G4 ACTIVE SOIC D 8 2500 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC2807N-1 ACTIVE PDIP P 8 50 Green (RoHS & CU NIPDAU Level-NC-NC-NC
no Sb/Br)
UCC2807N-2 ACTIVE PDIP P 8 50 Green (RoHS & CU NIPDAU Level-NC-NC-NC
no Sb/Br)
UCC2807PW-3 ACTIVE TSSOP PW 14 90 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC2807PWTR-3 ACTIVE TSSOP PW 14 2000 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC3807D-1 ACTIVE SOIC D 8 75 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC3807D-2 ACTIVE SOIC D 8 75 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC3807D-2G4 ACTIVE SOIC D 8 75 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC3807D-3 ACTIVE SOIC D 8 75 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC3807DTR-1 ACTIVE SOIC D 8 2500 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC3807DTR-2 ACTIVE SOIC D 8 2500 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC3807DTR-2G4 ACTIVE SOIC D 8 2500 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC3807DTR-3 ACTIVE SOIC D 8 2500 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC3807DTR-3G4 ACTIVE SOIC D 8 2500 Green (RoHS & CU NIPDAU Level-2-260C-1 YEAR
no Sb/Br)
UCC3807N-1 ACTIVE PDIP P 8 50 Green (RoHS & CU NIPDAU Level-NC-NC-NC
no Sb/Br)
UCC3807N-2 ACTIVE PDIP P 8 50 Green (RoHS & CU NIPDAU Level-NC-NC-NC
no Sb/Br)
UCC3807N-3 ACTIVE PDIP P 8 50 Green (RoHS & CU NIPDAU Level-NC-NC-NC
no Sb/Br)

Addendum-Page 1
 PACKAGE OPTION ADDENDUM
www.ti.com 4-Nov-2005

Orderable Device Status (1) Package Package Pins Package Eco Plan (2) Lead/Ball Finish MSL Peak Temp (3)
Type Drawing Qty
UCC3807N-3G4 ACTIVE PDIP P 8 50 Green (RoHS & CU NIPDAU Level-NC-NC-NC
no Sb/Br)
UCC3807PWTR-3 PREVIEW TSSOP PW 14 2000 TBD Call TI Call TI
(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)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS) or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)

(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.

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 2
 MECHANICAL DATA

MPDI001A – JANUARY 1995 – REVISED JUNE 1999

P (R-PDIP-T8) PLASTIC DUAL-IN-LINE

0.400 (10,60)
0.355 (9,02)
8 5

0.260 (6,60)
0.240 (6,10)

1 4
0.070 (1,78) MAX

0.325 (8,26)
0.020 (0,51) MIN
0.300 (7,62)

0.015 (0,38)

Gage Plane
0.200 (5,08) MAX
Seating Plane

0.125 (3,18) MIN 0.010 (0,25) NOM

0.100 (2,54) 0.430 (10,92)

MAX
0.021 (0,53)
0.010 (0,25) M
0.015 (0,38)

4040082/D 05/98

NOTES: A. All linear dimensions are in inches (millimeters).

B. This drawing is subject to change without notice.
C. Falls within JEDEC MS-001

For the latest package information, go to http://www.ti.com/sc/docs/package/pkg_info.htm

POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

 MECHANICAL DATA

MTSS001C – JANUARY 1995 – REVISED FEBRUARY 1999

PW (R-PDSO-G**) PLASTIC SMALL-OUTLINE PACKAGE

14 PINS SHOWN

0,30
0,65 0,10 M
0,19
14 8

0,15 NOM
4,50 6,60
4,30 6,20

Gage Plane

0,25
1 7
0°– 8°
A 0,75
0,50

Seating Plane

1,20 MAX 0,15 0,10

0,05

PINS **
8 14 16 20 24 28
DIM

A MAX 3,10 5,10 5,10 6,60 7,90 9,80

A MIN 2,90 4,90 4,90 6,40 7,70 9,60

4040064/F 01/97

NOTES: A. All linear dimensions are in millimeters.

B. This drawing is subject to change without notice.
C. Body dimensions do not include mold flash or protrusion not to exceed 0,15.
D. Falls within JEDEC MO-153

POST OFFICE BOX 655303 • DALLAS, TEXAS 75265

 IMPORTANT NOTICE

Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications,
enhancements, improvements, and other changes to its products and services at any time and to discontinue
any product or service without notice. Customers should obtain the latest relevant information before placing
orders and should verify that such information is current and complete. All products are sold subject to TI’s terms
and conditions of sale supplied at the time of order acknowledgment.

TI warrants performance of its hardware products to the specifications applicable at the time of sale in
accordance with TI’s standard warranty. Testing and other quality control techniques are used to the extent TI
deems necessary to support this warranty. Except where mandated by government requirements, testing of all
parameters of each product is not necessarily performed.

TI assumes no liability for applications assistance or customer product design. Customers are responsible for
their products and applications using TI components. To minimize the risks associated with customer products
and applications, customers should provide adequate design and operating safeguards.

TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right,
copyright, mask work right, or other TI intellectual property right relating to any combination, machine, or process
in which TI products or services are used. Information published by TI regarding third-party products or services
does not constitute a license from TI to use such products or services or a warranty or endorsement thereof.
Use of such information may require a license from a third party under the patents or other intellectual property
of the third party, or a license from TI under the patents or other intellectual property of TI.

Reproduction of information in TI data books or data sheets is permissible only if reproduction is without
alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Reproduction
of this information with alteration is an unfair and deceptive business practice. TI is not responsible or liable for
such altered documentation.

Resale of TI products or services with statements different from or beyond the parameters stated by TI for that
product or service voids all express and any implied warranties for the associated TI product or service and
is an unfair and deceptive business practice. TI is not responsible or liable for any such statements.

Following are URLs where you can obtain information on other Texas Instruments products and application
solutions:

Products Applications
Amplifiers amplifier.ti.com Audio www.ti.com/audio
Data Converters dataconverter.ti.com Automotive www.ti.com/automotive
DSP dsp.ti.com Broadband www.ti.com/broadband
Interface interface.ti.com Digital Control www.ti.com/digitalcontrol
Logic logic.ti.com Military www.ti.com/military
Power Mgmt power.ti.com Optical Networking www.ti.com/opticalnetwork
Microcontrollers microcontroller.ti.com Security www.ti.com/security
Telephony www.ti.com/telephony
Video & Imaging www.ti.com/video
Wireless www.ti.com/wireless

Mailing Address: Texas Instruments

Post Office Box 655303 Dallas, Texas 75265

Copyright  2005, Texas Instruments Incorporated