UNISONIC TECHNOLOGIES CO., LTD
TL431 LINEAR INTEGRATED CIRCUIT
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Copyright © 2011 Unisonic Technologies Co., Ltd QW-R103-003.AF
4PROGRAMMABLE PRECISION
REFERENCE
DESCRIPTION
The UTC TL431 is a three-terminal adjustable regulator with a
guaranteed thermal stability over applicable temperature ranges.
The output voltage may be set to any value between VREF
(approximately 2.5V) and 36V with two external resistors. It provides
very wide applications, including shunt regulator, series regulator,
switching regulator, voltage reference and others.
FEATURES
* Programmable output Voltage to 36V.
* Low dynamic output impedance 0.2Ω.
* Sink current capability of 1.0 to 100mA.
* Equivalent full-range temperature coefficient of 50ppm/ ℃
typical for operation over full rated operating temperature range.
ORDERING INFORMATION
Ordering Number Package Pin Assignment Packing
Lead Free Halogen Free 1 2 3 4 5 6 7 8
TL431K-AB3-R TL431G-AB3-R SOT-89 R A K - - - - - Tape Reel
TL431K-AE2-R TL431G-AE2-R SOT-23-3 K R A - - - - - Tape Reel
TL431K-AE3-R TL431G-AE3-R SOT-23 K R A - - - - - Tape Reel
TL431NSL-AE3-R TL431NSG-AE3-R SOT-23 R K A - - - - - Tape Reel
TL431NSL-AE2-R TL431NSG-AE2-R SOT-23-3 R K A - - - - - Tape Reel
TL431K-AF5-R TL431G-AF5-R SOT-25 X X K R A - - - Tape Reel
TL431K-S08-R TL431G-S08-R SOP-8 K A A X X A A R Tape Reel
TL431K-S08-T TL431G-S08-T SOP-8 K A A X X A A R Tube
TL431K-T92-B TL431G-T92-B TO-92 R A K - - - - - Tape Box
TL431K-T92-K TL431G-T92-K TO-92 R A K - - - - - Bulk
TL431K-T92-R TL431G-T92-R TO-92 R A K - - - - - Tape Reel
Note: Pin Code: K: Cathode A: Anode R: Reference X: No Connection
TL431 LINEAR INTEGRATED CIRCUIT
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MARKING
PACKAGE MARKING
SOT-23-3
SOT-23
3
431.
12
K: Lead Free
G: Halogen Free
SOT-23-3
SOT-23
(TL431NS)
3
431N
12
L: Lead Free
G: Halogen Free
SOT-25
321
431
54
K: Lead Free
G: Halogen Free
TL431 LINEAR INTEGRATED CIRCUIT
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BLOCK DIAGRAM
2.5V VREF
CATHODE
ANODE
REFERENCE
CATHODE (K)
ANODE(A)
REFERENCE (R)
TL431 LINEAR INTEGRATED CIRCUIT
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ABSOLUTE MAXIMUM RATINGS (Operating temperature range applies, unless otherwise specified)
PARAMETER SYMBOL RATINGS UNIT
Cathode Voltage VKA 37 V
Cathode Current Range(Continuous) IKA -100 ~ +150 mA
Reference Input Current Range IREF -0.05 ~ +10 mA
Power Dissipation
TO-92
PD
770 mW
SOT-89 800 mW
SOT-23/SOT-23-3/SOT-25 300 mW
SOP-8 600 mW
Operating Junction TJ +150 °C
Operating Ambient TOPR -40 ~ +85 °C
Storage Temperature TSTG -65 ~ +150 °C
Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged
Absolute maximum ratings are stress ratings only and functional device operation is not implied.
RECOMMENDED OPERATING CONDITIONS
PARAMETER SYMBOL MIN TYP MAX UNIT
Cathode Voltage VKA V
REF 36 V
Cathode Current IKA 1 100 mA
ELECTRICAL CHARACTERISTICS (TC= 25°C, unless otherwise specified.)
PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT
Reference Input Voltage VREF V
KA=VREF,IKA=10mA
TL431-A 2.483 2.495 2.507 V
TL431-1 2.470 2.495 2.520 V
TL431-2 2.520 - 2.545 V
TL431-3 2.445 - 2.470 V
Deviation of reference Input Voltage Over
temperature ΔT
ΔVREF VKA=VREF,IKA=10mA,
0°C ≤TA≤70°C 4.5 17 mV
Ratio of Change in Reference Input
Voltage to the Change in Cathode Voltage KA
REF
ΔV
ΔVIKA=10mA ΔVKA=10V~VREF -1.0 -2.7 mV/V
ΔVKA=36V~10V -0.5 -2.0 mV/V
Reference Input Current IREF I
KA=10mA, R1=10kΩ, R2=∞ 1.5 4 µA
Deviation of Reference Input Current Over
Full Temperature Range ΔT
ΔIREF IKA=10mA, R1=10kΩ, R2=∞,
TA =full Temperature 0.4 1.2 µA
Minimum Cathode Current for Regulation IKA
(
MIN
)
VKA=VREF 0.3 0.5 mA
Off-State Cathode Current IKA
(
OFF
)
VKA=36V, VREF=0 0.05 1.0 µA
Dynamic Impedance ZKA V
KA=VREF, IKA=1~ 100mA,f≤1.0kHz 0.15 0.5 Ω
TL431 LINEAR INTEGRATED CIRCUIT
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TEST CIRCUIT
INPUT VKA
VREF
IKA
UTC TL431
VKA=VREF×(1+R1/R2)+IREF×R1
For VKA=VREF For VKA≥VREF For IKA
(
OFF
)
APPLICATION CIRCUIT
VOUT=(1+R1/R2)×VREF VOUT=(1+R1/R2)×VREF
Minimum VOUT=VREF+5V VOUT=(1+R1/R2)×VREF
Shutdown Regulator Output Control of a Three
-Terminal Fixed Regulator Higher-current Shunt Regulator
UTC
TL431
RS
VOUT
VIN
IOUT
UTC
TL431
RS
IOUT
VIN VOUT
RCL
IOUT=VREF/RS IOUT =VREF/RCL
Constant-current Sink Current Limiting or Current Source
TL431 LINEAR INTEGRATED CIRCUIT
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■ TYPICAL CHARACTERISTICS
-1 1023
-200
0
400
200
600
800
-2
Cathode Voltage (V)
Cathode Current (μA)
01234567
0
1
2
3
4
5
6
7
Time (µs)
Input and Output Voltage (V)
Pulse Response
TA=25°C
Change In Reference Input Voltage (mV)
TA=25°C
VKA=VREF
Change in Reference Input Voltage vs.
Cathode Voltage
Cathode Current vs. Cathode Voltage
IKA(MIN
)
0 5 10 15 20 25 30 35 40 -1-1
Cathode Voltage (V)
-2 -1 0 1 2 3
-100
-75
-50
-25
0
25
50
75
100
125
Cathode Voltage (V)
Cathode Current (mA)
Cathode Current vs. Cathode Voltage
150 TA=25°C
VKA=VREF
0
-5
-10
-15
-20
-25
-30
-35
-40
IKA=10mA
TA=25°C
TL431 LINEAR INTEGRATED CIRCUIT
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UTC assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or
other parameters) listed in products specifications of any and all UTC products described or contained
herein. UTC products are not designed for use in life support appliances, devices or systems where
malfunction of these products can be reasonably expected to result in personal injury. Reproduction in
whole or in part is prohibited without the prior written consent of the copyright owner. The information
presented in this document does not form part of any quotation or contract, is believed to be accurate
and reliable and may be changed without notice.
