ZTL431/ZTL432
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ZTL431/ZTL432
COST EFFECTIVE ADJUSTABLE PRECISION SHUNT REGULATOR
Description
The ZTL431 and ZTL432 are three terminal adjustable shunt
regulators offering excellent temperature stability and output current
handling capability up to 100mA. The output voltage may be set to
any chosen voltage between 2.5 and 20 volts by selection of two
external divider resistors.
The devices can be used as a replacement for zener diodes in many
applications requiring an improvement in zener performance.
The ZTL432 has the same electrical specifications as the ZTL431 but
has a different pin out in SOT23 (F-suffix) and SOT23F (FF-suffix).
Both variants are available in two grades with initial tolerances of 1%
and 0.5% for the A and B grades, respectively.
These are functionally equivalent to the TL431/
TL432 except for
maximum operation voltage, and have an ambient temperature range
of -40°C to +125°C as standard.
Pin Assignments
(Top View)
SOT23, SOT23F
(ZTL431)
(Top View)
SOT23, SOT23F
(ZTL432)
(Top View)
SOT363
†Connected internally to substrate;
should be left floating or connected to Anode
(Top View)
SOT25 (SE5 Package)
(Top View)
SOT25 (E5 Package)
*must be left floating or
connected to pin 5
Features
Temperature Range ................ -40°C to +125°C
Reference Voltage Tolerance at +25°C
0.5%.......................................B grade
1% .........................................A grade
0.2Ω Typical Output Impedance
Sink Current Capability…….. 1mA to 100mA
Adjustable Output Voltage……VREF to 20V
Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
Halogen and Antimony Free. “Green” Device (Note 3)
An Automotive-
Compliant Part is Available Under Separate
Datasheet (ZTL431AQ, ZTL431BQ, ZTL432AQ, ZTL432BQ)
Applications
Opto-Coupler Linearization
Linear Regulators
Improved Zener
Variable Reference
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/quality/lead_free.html 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.
Anode
Cathode
Ref 2
1
3
Anode
Cathode
Ref 2
1
3
Cathode
Ref
N/CN/C
NC
Anode
3
2
1
4
5
6
Cathode
2
Anode
Cathode
N/C
3
15
4
Ref
N/C
2
Anode
Cathode
N/C
3
15
4
Ref
N/C*
NOT RECOMMENDED FOR NEW DESIGN
USE AS431
ZTL431/ZTL432
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ZTL431/ZTL432
Absolute Maximum Ratings (Voltages specified are relative to the Anode pin unless otherwise stated.)
Parameter
Rating
Unit
Cathode Voltage (VKA)
20 V
Continuous Cathode Current (IKA)
150 mA
Reference Input Current Range (IREF)
-50µA to +10mA
Operating Junction Temperature
-40 to +150
°C
Storage Temperature
-55 to +150
°C
Operation above the absolute maximum rating may cause device failure.
Operation at the absolute maximum ratings, for extended periods, may reduce device reliability.
Package Thermal Data
Package
θ
JA PDIS
TA = +25°C, TJ = +150°C
SOT23
380°C/W
330mW
SOT23F
138°C/W
900mW
SOT25
250°C/W
500mW
SOT363
380°C/W
330mW
Recommended Operating Conditions (@TA = +25°C, unless otherwise specified.)
Symbol
Parameter
Min
Max
Unit
VKA
Cathode Voltage
VREF
20
V
IKA
Cathode Current
1
100
mA
TA
Operating Ambient Temperature Range
-40
+125
°C
Electrical Characteristics (@TA = +25°C, unless otherwise specified.)
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
VREF Reference Voltage VKA = VREF
IKA = 10mA
ZTL43_A 2.475 2.5 2.525 V
ZTL43_B
2.487
2.5
2.513
VDEV Deviation of Reference Voltage Over Full
Temperature Range
VKA = VREF
IKA = 10mA
TA = 0 to +70°C
6
16
mV
TA = -40 to +85°C
14
34
TA = -40 to +125°C
14
34
VREF
VKA
Ratio of Change In Reference Voltage
To the Change In Cathode Voltage IKA = 10mA VKA = VREF to 10V -1.4 -2.7 mV/V
V
KA
= 10V to 20V -1.0 -2.0
IREF Reference Input Current IKA = 10mA, R1 = 10kΩ,
R2 = O/C (Open Circuit)
2 4 µA
IREF
IREF Deviation Over Full Temperature Range
IKA = 10mA
R1 = 10kΩ
R2 = O/C (Open
Circuit)
TA = 0 to +70°C
0.8 1.2
µA
TA = -40 to +85°C
0.8
2.5
TA = -40 to +125°C
0.8 2.5
I
KA(MIN)
Minimum Cathode Current for Regulation
VKA = VREF
0.4 0.6 mA
IKA(OFF) Off State Current VKA = 20V, VREF =
0V
0.1 0.5 µA
R
Z
Dynamic Output Impedance V
KA
= V
REF
, f = 0Hz 0.2 0.5
ZTL431/ZTL432
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ZTL431/ZTL432
Typical Characteristics
I
KA
= 10mA
V
REF
= V
KA
0
100
200
300
400
500
600
700
800
900
1000
0 25 50 75 100 125
SOT23-5
SOT23
SC70-6
SOT23F
Ambient Temperature (°C)
Power Dissipation (mW)
Reference Voltage vs. Temperature
Dynamic Impedance vs. Frequency
Power Dissipation Derating
SOT25
SOT36
3
ZTL431/ZTL432
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ZTL431/ZTL432
Typical Characteristics (Cont.)
I
KA
I
KA
I
KA
V
KA
V
KA
V
REF
< V
KA
< 20, I
KA
= 10mA, T
A
= 25°C
V
KA
V
KA
Stability Boundary Condition
0
10
20
30
40
50
60
70
80
90
100
10.0E-12 100.0E-12 1.0E-9 10.0E-9 100.0E-9 1.0E-6
Load Capacitance (F)
Cathode Current(mA)
Gain vs. Frequency
0
10
20
30
40
50
60
100 1000 10000 100000 1000000
Frequency (Hz)
Gain (dB)
S
S
Stable
S
a
b
b
e
e
Stable
Pulse Response
Test Circuit for Stabilty Boundary Conditions
Test Circuit for Pulse Response
Test Circuit for Open Loop Voltage Gain
V
REF
< V
KA
< 20V, I
KA
= 10mA, T
A
= +25°C
Test Circuit for Stability Boundary Conditions
ZTL431/ZTL432
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ZTL431/ZTL432
Application Circuits
V
ON
~2V
V
OFF
=V
+
V
TH
=2.5V
Output
V+
Input
R1
R2
V
OUT
V
OUT
V+
V
REF
V
REF
R1
R2
V
OUT
V
OUT
V+
V
REF
V
REF
R1
R2
V
OUT
V
OUT
V+
V
REF
V
REF
V
OUT(MIN)
=V
REF
+ V
REG
InOut
Common
ZSR***
0.01µF
30Ω
R1
R2
V
REF
V+
V
OUT
V
OUT
V
REF
R1
R1
R2b
R2a
V
REF
V
REF
V
REF
V
REF
V+
Output
Shunt regulator
Outputcontrol of athree
terminal fixed regulator
Single supply comparator
with temperature
compensated threshold
Highercurrent shunt
regulator
Series regulator
Over voltage / under voltage
protection circuit
R1
R1
R2
R2
ZTL431/ZTL432
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ZTL431/ZTL432
DC Test Circuits
Notes
Deviation of reference input voltage, VDEV, is defined as the
maximum variation of the reference input voltage over the full
temperature range.
The average temperature coefficient of the reference input
voltage, VREF is defined as:
VREF(ppm/°C) = VDEV × 1,000,000
VREF(T1-T2)
The dynamic output impedance, Rz, is defined as:
RZ = ΔVZ
ΔIZ
When the device is programmed with two external resistors, R1
and R2, (Figure 2), the dynamic output impedance of the
overall circuit, R'z, is defined as:
R'Z = RZ (1 + R1 )
R2
Stability Boundary
The ZTL431 and ZTL432 are stable with a range of capacitive
loads. A zone of instability exists as demonstrated in the typical
characteristic graph on page 4. The graph shows typical
conditions. To ensure reliable stability, a capacitor of 4.7nF or
greater is recommended between anode and cathode.
VMAX
VMIN
VDEV = VMAX - VMIN
ZTL431/ZTL432
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ZTL431/ZTL432
Ordering Information
E5/SE5 : SOT25
ZTL43X X X X
Packing
Package
TA : 7" Tape & Reel
Pinout Variation Tolerance
A : ±1.0%
B : ±0.5% FF : SOT23F
F : SOT23
H6 : SOT363
1 : Standard Pin Out
2 : Reversed Pin Out
in SOT23/SOT23F
Tol. Part Number Package Part Mark Status Reel Size
Tape Width
(mm)
Quantity per
Reel
1%
ZTL431AE5TA SOT25 31A Active 7”, 180mm 8 3,000
ZTL431AFFTA SOT23F 31A Active 7”, 180mm 8 3,000
ZTL431AFTA SOT23 31A Active 7”, 180mm 8 3,000
ZTL431AH6TA SOT363 31A Active 7”, 180mm 8 3,000
ZTL431ASE5TA SOT25 S2A Active 7”, 180mm 8 3,000
ZTL432AFFTA SOT23F 32A Active 7”, 180mm 8 3,000
ZTL432AFTA SOT23 32A Active 7”, 180mm 8 3,000
0.5%
ZTL431BE5TA SOT25 31B Active 7”, 180mm 8 3,000
ZTL431BFFTA SOT23F 31B Active 7”, 180mm 8 3,000
ZTL431BFTA SOT23 31B Active 7”, 180mm 8 3,000
ZTL431BH6TA SOT363 31B Active 7”, 180mm 8 3,000
ZTL432BFFTA SOT23F 32B Active 7”, 180mm 8 3,000
ZTL432BFTA SOT23 32B Active 7”, 180mm 8 3,000
ZTL431/ZTL432
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ZTL431/ZTL432
Marking Information
(1) SOT23 and SOT23F
(Top View)
(2) SOT25
(Top View)
(3) SOT363
(Top View)
Part Number
Identification Code
ZTL431AFFTA
31A
ZTL431AFTA
31A
ZTL432AFFTA
32A
ZTL432AFTA
32A
ZTL431BFFTA
31B
ZTL431BFTA
31B
ZTL432BFFTA
32B
ZTL432BFTA
32B
Part Number
Identification Code
ZTL431AE5TA
31A
ZTL431ASE5TA
S2A
ZTL431BE5TA
31B
Part Number
Identification Code
ZTL431AH6TA
31A
ZTL431BH6TA
31B
1
23
XXX
12 3
4
5
XXX
123
4
5
6
XXX
XXX : Identification Code
XXX : Identification Code
XXX : Identification Code
ZTL431/ZTL432
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ZTL431/ZTL432
Package Outline Dimensions
Please see http://www.diodes.com/package-outlines.html for the latest version.
(1) Package Type: SOT23
J
K1 K
L1
GAUGE PLANE
0.25
H
L
M
All 7°
A
CB
D
G
F
a
(2) Package Type: SOT23F
E1
D
b
E
L1
A
R
b
e1
e
c
k
L
A1
SOT23
Dim
Min
Max
Typ
A
0.37
0.51
0.40
B
1.20
1.40
1.30
C
2.30
2.50
2.40
D
0.89
1.03
0.915
F
0.45
0.60
0.535
G
1.78
2.05
1.83
H
2.80
3.00
2.90
J
0.013
0.10
0.05
K
0.890
1.00
0.975
K1
0.903
1.10
1.025
L
0.45
0.61
0.55
L1
0.25
0.55
0.40
M
0.085
0.150
0.110
a
--
All Dimensions in mm
SOT23F
Dim
Min
Max
Typ
A
0.80
1.00
0.90
A1
0.00
0.10
0.01
b
0.35
0.50
0.44
c
0.10
0.20
0.16
D
2.80
3.00
2.90
e
0.95 REF
e1
1.90 REF
E
2.30
2.50
2.40
E1
1.50
1.70
1.65
k
1.20
-
-
L
0.30
0.65
0.50
L1
0.30
0.50
0.40
R
0.05
0.15
-
All Dimensions in mm
ZTL431/ZTL432
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Package Outline Dimensions (Cont.)
Please see http://www.diodes.com/package-outlines.html for the latest version.
(3) Package Type: SOT363
e
D
L
E1
b
E
F
A2
A1
ca
(4) Package Type: SOT25
SOT363
Dim
Min
Max
Typ
A1
0.00
0.10
0.05
A2
0.90
1.00
1.00
b
0.10
0.30
0.25
c
0.10
0.22
0.11
D
1.80
2.20
2.15
E
2.00
2.20
2.10
E1
1.15
1.35
1.30
e
0.650 BSC
F
0.40
0.45
0.425
L
0.25
0.40
0.30
a
0°
8°
--
All Dimensions in mm
SOT25
Dim
Min
Max
Typ
A
0.35
0.50
0.38
B
1.50
1.70
1.60
C
2.70
3.00
2.80
D
-
-
0.95
H
2.90
3.10
3.00
J
0.013
0.10
0.05
K
1.00
1.30
1.10
L
0.35
0.55
0.40
M
0.10
0.20
0.15
N
0.70
0.80
0.75
α
-
All Dimensions in mm
A
M
JL
D
BC
H
KN
ZTL431/ZTL432
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Suggested Pad Layout
Please see http://www.diodes.com/package-outlines.html for the latest version.
(1) Package Type: SOT23
X
Y
Y1 C
X1
(2) Package Type: SOT23F
X
Y
Y1
C
(3) Package Type: SOT363
Y1 G
Y
X
C
Dimensions
Value (in mm)
C
2.0
X
0.8
X1
1.35
Y
0.9
Y1
2.9
Dimensions
Value
(in mm)
C
0.95
X
0.80
Y
1.110
Y1
3.000
Dimensions
Value
(in mm)
C
0.650
G
1.300
X
0.420
Y
0.600
Y1
2.500
ZTL431/ZTL432
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ZTL431/ZTL432
Suggested Pad Layout (Cont.)
Please see http://www.diodes.com/package-outlines.html for the latest version.
(4) Package Type: SOT25
Dimensions
Value
Z
3.20
G
1.60
X
0.55
Y
0.80
C1
2.40
C2
0.95
X
Z
Y
C1
C2
C2
G
ZTL431/ZTL432
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ZTL431/ZTL432
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WITH REGARDS TO ANY INFORMATION CONTAINED IN THIS DOCUMENT, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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INTELLECTUAL PROPERTY RIGHTS (AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY JURISDICTION).
2. The Information contained herein is for informational purpose only and is provided only to illustrate the operation of Diodes products
described herein and application examples. Diodes does not assume any liability arising out of the application or use of this document or any
product described herein. This document is intended for skilled and technically trained engineering customers and users who design with Diodes
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