A Product Line of

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ZXRE160
0.6V ENHANCED ADJUSTABLE PRECISION SHUNT REGULATOR

Description Pin Assignments

The ZXRE160 is a 5-terminal adjustable shunt regulator offering ZXRE160_H5 (SC70/SOT353) and
excellent temperature stability and output handling capability. This ZXRE160_ET5 (TSOT25)
device offers an enhancement to the ZXRE060 part for use in a Top view

comparator mode applications.

NEW PRODUCT

In shunt regulator mode, the ZXRE160 simplifies the design of

isolated low voltage DC-DC regulators. With its low 0.6V FB pin, it can
control the regulation of rails as low 0.6V. This makes the part ideal
for state of the art microprocessor, DSP and PLD core voltage
POL converters.

The device open-collector output can operate from 0.2V to 18V and
ZXRE160_FT4 (X2-DFN1520-6)
regulated output voltage can be set by selection of two external
Top view
divider resistors. Separating the input from the open collector output
enables the ZXRE160 to be used to make low-cost low drop-out
PGND 1 6 IN
regulators operating at low input voltages.

The ZXRE160 is available in two grades with initial tolerances of 0.5%

N/C 2 5 GND
and 1% for the A and standard grades respectively. It is available in
space saving low profile 5 pin SC70/SOT353, thin TSOT25 and very
OUT 3 4 FB
small DFN1520 packages.

Exposed flag floating or

Features connect to GND

• Low reference voltage (VFB = 0.6V)

• -40°C to +125°C temperature range
• Reference voltage tolerance at +25°C Applications
• 0.5% ZXRE160A
• Isolated DC-DC converters
• 1% ZXRE160
• Core voltage POL
• Typical temperature drift
• Low Voltage Low-Dropout linear regulators
• <4 mV (0°C to +70°C)
• Shunt regulators
• <6 mV (-40°C to +85°C)
• Adjustable voltage reference
• <12mV (-40°C to +125°C)
• 0.2V to 18V open-collector output
• High power supply rejection
• (>45dB at 300kHz)
• Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
• Halogen and Antimony Free. “Green” Device (Note 3)

Notes: 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. See http://www.diodes.com for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green" and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.

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Typical Applications Circuit

NEW PRODUCT

Pin Descriptions

Package Name
Pin Number
Pin Name Function
SC70/ SOT353,
X2-DFN1520-6
TSOT25
Power Ground: Ground return for emitter of output transistor: Connect PGND and
PGND 1 1
GND together.
— — 2 No connection
Output: Connect a capacitor close to device between OUT and GND for closed loop
OUT 5 3
stability. See the Applications Information section.
FB 4 4 Feedback Input. Threshold voltage 600mV nominal.
Analog Ground: Ground return for reference and amplifier: Connect GND and PGND
GND 2 5
together.
IN 3 6 Supply Input: Connect a 0.1μF ceramic capacitor close to the device from IN to GND.
— — Flag Floating or connect to GND

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Functional Block Diagram

NEW PRODUCT

The ZXRE160 differs from most other shunt regulators in that it auxiliary rail voltage, or below the minimum VIN voltage. This
has separate input and output pins and a low voltage reference. allows it to operate as a low-dropout voltage regulator for
This enables it to regulate rails down to 600mV and makes the microprocessor/DSP/PLD cores.
part ideal for isolated power supply applications that use As with other shunt regulators (and shunt references), the
opto-couplers in the feedback loop and where the open-collector ZXRE160 compares its internal amplifier FB pin to a high
output is required to operate down to voltages as low as 200mV. accuracy internal reference; if FB is below the reference then OUT
The wide input voltage range of 2V to 18V and output voltage turns off, but if FB is above the reference then OUT sinks current
range of 0.2V to 18V enables the ZXRE160 to be powered from – up to a maximum of 15mA.
an auxiliary rail, while controlling a master rail which is above the

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Absolute Maximum Ratings (Voltages to GND, @TA = +25°C, unless otherwise specified.)

Symbol Parameter Rating Unit

VIN IN Voltage relative to GND 20 V
VOUT OUT Voltage relative to GND 20 V
VFB FB Voltage relative to GND 20 V
NEW PRODUCT

PGND PGND Voltage relative to GND -0.3 to +0.3 V

IOUT OUT Pin Current 20 mA
TJ Operating Junction Temperature -40 to 150 °C
TST Storage Temperature 55 to 150 °C
These are stress ratings only. Operation outside the absolute maximum ratings may cause device failure.
Operation at the absolute maximum rating for extended periods may reduce device reliability.
Semiconductor devices are ESD sensitive and may be damaged by exposure to ESD events.
Suitable ESD precautions should be taken when handling and transporting these devices.

Package Thermal Data

PDIS
Package θJA
TA = 25°C, TJ = 150°C
SC70/SOT353 400°C/W 310mW
TSOT25 250°C/W 500mW
X2-DFN1520-6 TBD TBD

Recommended Operating Conditions (@TA = +25°C, unless otherwise specified.)

Symbol Parameter Min Max Units

VIN IN Voltage Range (0 to +125°C) 2 18
VIN IN Voltage Range (-40°C to 0°C) 2.2 18 V
VOUT OUT Voltage Range 0.2 18
IOUT OUT Pin Current 0.3 15 mA
Operating Ambient Temperature
TA -40 +125 °C
Range

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Electrical Characteristics (@TA = +25°C, VDD = 3V, unless otherwise specified.)

TA = +25°C, VIN = 3.3V, VOUT = VFB, IOUT = 5mA, unless otherwise specified.) (Note 4)
Symbol Parameter Conditions Min Typ Max Units
ZXRE160A 0.597 0.6 0.603
ZXRE160 0.594 0.6 0.606
NEW PRODUCT

ZXRE160A 0.595 0.605

TA = 0°C to +85°C
ZXRE160 0.592 0.608

VFB Feedback voltage ZXRE160A 0.594 0.606 V

TA = -40°C to +85°C
ZXRE160 0.591 0.609

ZXRE160A 0.593 0.607

TA = -40°C to +125°C
ZXRE160 0.590 0.610

Feedback pin load 3.8 6

FBLOAD IOUT = 1 to 15mA mV
regulation TA = -40 to +125°C 10
Feedback pin line VIN = 2V to 18V 0.3 1
FBLINE mV
regulation VIN = 2.2V to 18V TA = -40 to +125°C 1.5
VOUT = 0.2V to 18V, 1
Output voltage
FBOVR IOUT = 1mA mV
regulation TA = -40 to +125°C 1.5
(Ref. Figure 1)
-45
IFB FB input bias current VIN = 18V TA = -40 to +125°C -200 0 nA
VFB = 0.7V -50 50

VIN = 2V to 18V 0.35 0.7

IOUT = 0.3mA mA
VIN = 2.2V to 18V TA = -40 to +125°C 1

IIN Input current VIN = 2V to 18V 0.48 1

IOUT = 10mA
VIN = 2.2V to 18V TA = -40 to +125°C 1.5 mA

VIN = 18V, IOUT = 0.3mA VFB = 0.7V 3

VIN = 18V, 0.1

IOUT(LK) OUT leakage current VOUT = 18V, µA
TA = +125°C 1
VFB =0V
Dynamic Output IOUT = 1 to 15mA 0.25 0.4
ZOUT Ω
Impedance f < 1kHz TA = -40 to +125°C 0.6
Power supply rejection F = 300kHz
PSRR >45 dB
ratio VAC = 0.3VPP
Amplifier Unity Gain
BW Ref: Figure 2 600 kHz
Frequency
Amplifier
G 5000 mA/V
Transconductance
Note: 4. Production testing of the device is performed at +25°C. Functional operation of the device and parameters specified over the operating temperature
range are guaranteed by design, characterization and process control.

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Typical Characteristics
NEW PRODUCT

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Typical Operating Characteristics

200 225 200 225

V OUT = 0.6V V OUT = 6V

COUT = 2.2uF COUT = 0.22uF
150 180 150 180
NEW PRODUCT

100 135 100 135

Phase (deg)
Phase (deg)

Gain (dB)
Gain (dB)

50 90 50 90

0 45 0 45
Gain Gain
Phas e Phase

-50 0 -50 0
1 10 100 1k 10k 100k 1M 1 10 100 1k 10k 100k 1M
Frequency (Hz) Frequency (Hz)

Gain and Phase vs Frequency, VOUT=0.6V Gain and Phase vs Frequency, V OUT=6V

Figure 2. Test Circuits for Gain and Phase Plots

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ZXRE160

Application Information

The following show some typical application examples for the ZXRE160.
Figure 3 shows a typical configuration for the ZXRE160 in comparator
mode.
Here the comparator switches low when:
NEW PRODUCT

VFB (R1 + R 2 )
VM ≥
R2
Alternative values of R1, R2 may be used to provide different threshold
voltages. R3 can also be adjusted to set the bias current for different
values of VM. R2 should be kept as low as possible to minimize errors
due to the bias current of the FB pin.

This circuit has no hysteresis, so a small capacitor of approx.4.7nF

between FB and GND is recommended to provide cleaner transitions at
the output.

Figure 3. 15V Supply Monitor

In shunt regulator mode it is necessary to include the compensation capacitor C2 to guarantee stability. C2 may range in value from 0.1µF to
10µF depending on the application. The minimum value of C2 can be determined from the following equation (resistor values are in kΩ):

R2
C2MIN ≥ μF
R 3 (R1 + R 2 )

Both C1 and C2 should be as close to the ZXRE160 as possible and connected to it with the shortest possible track. In the case of Figure 10 and
Figure 11, it means the opto-coupler will have to be carefully positioned to enable this.

⎛ R1 ⎞
VOUT = VREF VOUT = VREF ⎜1 + ⎟
⎝ R2 ⎠

VIN − VOUT VIN − VOUT

R3 = R3 =
IR3 IR3

Figure 4. 0.6V Shunt Regulator Figure 5. 1.0V Shunt Regulator

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Application Information (cont.)

NEW PRODUCT

VOUT = VREF ⎛ R1 ⎞
VOUT = VREF ⎜1 + ⎟
⎝ R2 ⎠
Figure 6. 0.6V Series LDO Regulator
Figure 7. 1.0V Series LDO Regulator

Design guide:

1. Determine IOUT and choose a suitable transistor taking power dissipation into consideration.
IOUT(max)
2. Determine IB from IB =
(hFE(min) + 1)

3. Determine IR3 from IR3 ≥ IB + IKA(min) . The design of the ZXRE160 effectively means there is no IKA(min) limitation as in conventional

references. There is only an output leakage current which is a maximum of 1µA. Nevertheless, it is necessary to determine an IKA(min) to
ensure that the device operates within its linear range at all times. IKA(min) ≥ 10µA should be adequate for this.

4. Determine R3 from R3 = VIN − ( VOUT + VBE ) .

IR3

Although unlikely to be a problem, ensure that IR3 ≤ 15 mA.

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Application Information (cont.)

⎛ R1 ⎞
VOUT = VREF ⎜1 + ⎟
⎝ R2 ⎠
NEW PRODUCT

VOUT ≥ 0.2V + VBE

VIN − VOUT
R3 =
IR3

Figure 8. 1V Current-Boosted Shunt Regulator

Design guide

1. Determine IOUT and choose a suitable transistor taking power dissipation into consideration.

2. Determine IB from I = IOUT(max)

B
(hFE(min) + 1)

3. Determine IR3 from IR3 = IOUT(max)

VIN − VOUT
4. Determine R3 from R3 =
IR3

5. It is best to let the ZXRE160 supply as much current as it can before bringing Q1 into conduction. Not only does this minimize the strain on
Q1, it also guarantees the most stable operation. Choose a nominal value between 10mA and <15mA for this current, IR4.
VBE
Calculate R4 from R4 =
IR4

VOUT goes low and LED is lit when monitored supply

⎛ R1 ⎞
VM > VREF ⎜ 1 + ⎟
⎝ R2 ⎠

V − ( VF + 0.2)
R3 = IN
IR3

15mA ≥ IR3 ≤ IF(MAX)

VF and IF are forward voltage drop and current of LED1.

Figure 9. 1.15V Over-Voltage Indicator

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Application Information (cont.)

NEW PRODUCT

⎛ R1 ⎞
VOUT = VREF VOUT = VREF ⎜1 + ⎟
⎝ R2 ⎠

VIN − ( VF + 0.2)
R3 = VIN − ( VF + 0.2)
IR3 R3 =
IR3

15mA ≥ IR3 ≤ IF(MAX) 15mA ≥ IR3 ≤ IF(MAX)

Figure 10. Opto-Isolated 0.6V Shunt Regulator Figure 11. Opto-Isolated 1.0V Shunt Regulator

VF and IF are forward voltage drop and forward current respectively for the optocoupler LED

More applications information is available in the following publications which can be found on Diodes’ web site.

AN58 - Designing with Diodes’ References – Shunt Regulation

AN59 - Designing with Diodes’ References – Series Regulation
AN60 - Designing with Diodes’ References – Fixed Regulators and Opto-Isolation
AN61 - Designing with Diodes’ References – Extending the operating voltage range
AN62 - Designing with Diodes’ References – Other Applications
AN63 - Designing with Diodes’ References – ZXRE060 Low Voltage Regulator

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Ordering Information
NEW PRODUCT

Identification
Tol. Part Number Package Reel Size Tape Width Quantity/Reel
Code
ZXRE160AET5TA TSOT25 R8 7”, 180mm 8mm 3000
0.5% ZXRE160AH5TA SC70/SOT353 R9 7”, 180mm 8mm 3000
ZXRE160AFT4-7 DFN1520H4-6 R8 7”, 180mm 8mm 3000
ZXRE160ET5TA TSOT25 Z8 7”, 180mm 8mm 3000
1% ZXRE160H5TA SC70/SOT353 Z9 7”, 180mm 8mm 3000
ZXRE160FT4-7 X2-DFN1520-6 Z8 7”, 180mm 8mm 3000

Marking Information

1. TSOT25, SC70/SOT353

2. X2-DFN1520-6

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Package Outline Dimensions (All dimensions in mm.)

TSOT25
TSOT25
D Dim Min Max Typ
e1 A − 1.00 −
A1 0.01 0.10 −
A2 0.84 0.90 −
NEW PRODUCT

D − − 2.90
E1 E E − − 2.80
E1 − − 1.60
c L2 b 0.30 0.45 −
θ c 0.12 0.20 −
L
4x θ1 e − − 0.95
e
e1 − − 1.90
5x b
L 0.30 0.50
L2 − − 0.25
A A2 θ 0° 8° 4°
θ1 4° 12° −
A1 All Dimensions in mm

SC70/SOT353
A
SOT353
Dim Min Max
A 0.10 0.30
B C B 1.15 1.35
C 2.00 2.20
D 0.65 Typ
F 0.40 0.45
H 1.80 2.20
H
J 0 0.10
K
K 0.90 1.00
M L 0.25 0.40
M 0.10 0.22
J α 0° 8°
D F L
All Dimensions in mm

X2-DFN1520-6

A3
A
SEATING PLANE
X2-DFN1520-6
A1 Dim Min Max Typ
D A − 0.40 −
e
A1 0 0.05 −
L
A3 − − 0.13
b 0.20 0.30 −
D 1.45 1.575 −
D2 1.00 1.20 −
e − − 0.50
E E2 E 1.95 2.075 −
D2 E2 0.70 0.90 −
L 0.25 0.35 −
All Dimensions in mm

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Suggested Pad Layout

TSOT25
C C

Dimensions Value (in mm)

C 0.950
NEW PRODUCT

X 0.700
Y1 Y 1.000
Y1 3.199

Y (5x)

X (5x)
SC70/SOT353

C2 C2

Dimensions Value (in mm)

Z 2.5
G 1.3
G C1 X 0.42
Z Y 0.6
C1 1.9
Y C2 0.65

X2-DFN1520-6

C1
C

G2
G1

Dimensions Value (in mm)

Z 1.25
G1 0.45
X1
G2 0.15
X1 1.10
C 0.50
C1 0.25

G2
Z

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NEW PRODUCT

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