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
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
Product specification 1997 Feb 25
INTEGRATED CIRCUITS
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2
1997 Feb 25 853–1927 17795
DESCRIPTION
The TL431 and TL431A are 3-terminal adjustable shunt regulators
with specified thermal stability over applicable automotive and
commercial temperature ranges. The output voltage may be set to
any value between VREF (approximately 2.5V) and 36V with two
external resistors (see Figure 4). These devices have a typical
output impedance of 0.2Ω. Active output circuitry provides a very
sharp turn-on characteristic, making these devices excellent
replacements for zener diodes in many applications like on-board
regulation, adjustable power supplies and switching power supplies.
The TL431C and TL431AC are characterized for operation from
0°C to +70°C; the TL431I and TL431AI are characterized for
operation from –40°C to +85°C.
FEATURES
•Equivalent full-range temperature coefficient: 30ppm/°C
•0.2Ω typical output impedance
•Sink current capability: 1mA to 100mA
•Low output noise
•Adjustable output voltage: VREF to 36V
PIN CONFIGURATIONS
1
2
3
45
6
7
8CATHODE
ANODE
ANODE
NC
REF
ANODE
ANODE
NC
CATHODE
ANODE
REF
M, D Package
SOT96-1
1
2
3
45
6
7
8CATHODE
NC
NC
NC
REF
NC
ANODE
NC
N, P Package
SOT97-1
Z, LP, U Package
SOT54
SL01167
TOP VIEW
TOP VIEW
Figure 1. Pin Configuration
ORDERING INFORMATION
DESCRIPTION TEMPERATURE
RANGE INDUSTRY STANDARD
PART NUMBER ORDER CODE DWG #
3-Pin Plastic TO92 20°C to +70°C TL431CLP TL431CLPU SOT54
3-Pin Plastic TO92 20°C to +70°C TL431ACLP TL431ACLPU SOT54
3-Pin Plastic TO92 2–40°C to +85°C TL431ILP TL431ILPU SOT54
3-Pin Plastic TO92 2–40°C to +85°C TL431AILP TL431AILPU SOT54
3-Pin Plastic TO92 20°C to +70°C LM431ACZ LM431ACZU SOT54
8-Pin Plastic Small Outline (SO) package 0°C to +70°C TL431CD TL431CD SOT96-1
8-Pin Plastic Small Outline (SO) package –40°C to +85°C TL431ID TL431ID SOT96-1
8-Pin Plastic Small Outline (SO) package 0°C to +70°C TL431ACD TL431ACD SOT96-1
8-Pin Plastic Small Outline (SO) package –40°C to +85°C TL431AID TL431AID SOT96-1
8-Pin Plastic Small Outline (SO) package 0°C to +70°C LM431ACM LM431ACMD SOT96-1
8-Pin Plastic Dual In-Line package (DIP) 0°C to +70°C TL431CP TL431CPN SOT97-1
8-Pin Plastic Dual In-Line package (DIP) –40°C to +85°C TL431IP TL431IPN SOT97-1
8-Pin Plastic Dual In-Line package (DIP) 0°C to +70°C TL431ACP TL431ACPN SOT97-1
8-Pin Plastic Dual In-Line package (DIP) –40°C to +85°C TL431AIP TL431AIPN SOT97-1
NOTE:
1. SYMBOL INFORMATION: Parts will be marked with product name including temperature and electrical grade desginators, but not the
package identifier .
2. TO92 is normally shipped in bulk, i.e., in plastic bags (containing 1,000 parts), 5 bags per box. Tape and reel (or ammo box) is an option.
See page 15 for information.
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 3
ABSOLUTE MAXIMUM RATINGS
SYMBOL PARAMETER RATING UNITS
VKA Cathode voltage (see Note 1) 37 V
Continuous cathode current range –100 to +150 mA
Reference input current range 0.05 to 10 mA
Operating free-air temperature range
Tamb C suffix 0 to +70 °C
I suffix –40 to +85 °C
TSTG Temperature storage range –65 to 150 °C
Lead temperature 1.6mm (1/16 in.) from case for 10 sec: D or P pkgs 260 °C
Lead temperature 1.6mm (1/16 in.) from case for 60 sec: LP pkg 300 °C
NOTE:
1. Voltage values are with respect to the anode terminal unless otherwise noted.
RECOMMENDED OPERATING CONDITIONS
SYMBOL PARAMETER MIN MAX UNITS
VKA Cathode voltage VREF 36 V
IKCathode current 1 100 mA
Table 1. Dissipation Rating Table – Free-Air Temperature
Package Derating Factor Above Tamb
= 25°CTamb = 25°C
Power Rating Tamb = 70°C
Power Rating Tamb = 85°C
Power Rating
D 5.8mW/°C 725mW 464mW 429mW
LP 6.2mW/°C 775mW 496mW 403mW
P 8.0mW/°C 1000mW 640mW 520mW
CATHODE
REF
ANODE
Q5
QD6
R5
3.28K
R11
2.4K
Q11 Q10
R9
800
R8
1000
Q9
C2
20p
R10
7.2K
R7
320
Q8 QD2
R1
10K
R2
150
Q2
Q1
Qq1
C1
20p
R3
800
R4
800
Q4
Q7
SL01188
Q3
Figure 2. Equivalent Schematic
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 4
DC ELECTRICAL CHARACTERISTICS
25°C free-air temperature, unless otherwise stated.
TEST
LIMITS
SYMBOL PARAMETER TEST
CKT
TEST CONDITIONS TL431AC TL431C/LM431AC UNIT
CKT
MIN TYP MAX MIN TYP MAX
VREF Reference input voltage Fig. 3 VKA = VREF, IK = 10mA 2470 2495 2520 2440 2495 2550 mV
VREF(dev) Deviation of reference input
voltage over full
temperature range3Fig. 3 VKA = VREF, IK = 10mA,
Tamb = full range24 15 4 17 mV
VREF Ratio of change in reference
in
p
ut voltage to the change
Fig 4
I = 10mA
∆VKA = 10V – VREF –1.4 –2.7 –1.4 –2.7
mV/V
REF
VKA
in ut
voltage
to
the
change
in cathode voltage
Fig
.
4
I
K =
10mA
∆VKA = 36V – 10V –1 –2 –1 –2
mV/V
IREF Reference input current Fig. 4 IK = 10mA, R1 = 10kΩ, R2 = ∞2 4 2 4 µA
IREF(dev) Deviation of reference input
current over full temperature
range3Fig. 4 IK = 10mA, R1 = 10kΩ, R2 = ∞,
Tamb = full range20.8 1.2 0.4 1.2 µA
IMIN Minimum cathode current
for regulation Fig. 3 VKA = VREF 0.4 0.6 0.4 1 mA
IOFF Off-state cathode current Fig. 5 VKA = 36V, VREF = 0 0.1 0.5 0.1 1 µA
| ZKA | Dynamic impedance4Fig. 3 VKA = VREF, IK = 1mA to 100mA,
f ≤ 1kHz 0.2 0.5 0.2 0.5 Ω
25°C free-air temperature, unless otherwise stated.
TEST
LIMITS
SYMBOL PARAMETER TEST
CKT
TEST CONDITIONS TL431AI TL431I UNIT
CKT
MIN TYP MAX MIN TYP MAX
VREF Reference input voltage Fig. 3 VKA = VREF, IK = 10mA 2470 2495 2520 2440 2495 2550 mV
VREF(dev) Deviation of reference input
voltage over full
temperature range3Fig. 3 VKA = VREF, IK = 10mA,
Tamb = full range25 25 5 30 mV
VREF Ratio of change in reference
in
p
ut voltage to the change
Fig 4
I = 10mA
∆VKA = 10V – VREF –1.4 –2.7 –1.4 –2.7
mV/V
REF
VKA
in ut
voltage
to
the
change
in cathode voltage
Fig
.
4
I
K =
10mA
∆VKA = 36V – 10V –1 –2 –1 –2
mV/V
IREF Reference input current Fig. 4 IK = 10mA, R1 = 10kΩ, R2 = ∞2 4 2 4 µA
IREF(dev) Deviation of reference input
current over full temperature
range3Fig. 4 IK = 10mA, R1 = 10kΩ, R2 = ∞,
Tamb = full range20.8 2.5 0.8 2.5 µA
IMIN Minimum cathode current
for regulation Fig. 3 VKA = VREF 0.4 0.7 0.4 1 µA
IOFF Off-state cathode current Fig. 5 VKA = 36V, VREF = 0 0.1 0.5 0.1 1 µA
| ZKA | Dynamic impedance4Fig. 3 VKA = VREF, IK = 1mA to 100mA,
f ≤ 1kHz 0.2 0.5 0.2 0.5 Ω
NOTES:
2. Full temperature range is –40°C to +85°C for the TL431I and TL431AI, and 0°C to +70°C for the TL431C and TL431AC.
3. The deviation parameters VREF(dev) and IREF(dev) are defined as the differences between the maximum and minimum values obtained over
the rated termperature range. The average full-range temperature coefficient of the reference input voltage, αVREF, is defined as:
|VREF |ppm
degCVREF(dev)
VREF at 25oC106
Tamb VREF(dev)
Max VREF
Min VREF
∆Tamb
where ∆Tamb is the rated operating free-air temperature range of the device.
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 5
αVREF can be positive or negative depending on whether minimum VREF of maximum VREF, respectively, occurs at the lower temperature.
Example: Max VREF = 2496mV at 30°C, Min VREF = 2492mV at 0°C, VREF = 2495mV at 25°C, DTA = 70°C for TL431C.
|VREF |+ǒ4mV
2495mVǓ@106
70oC+23ppmńoC
Because minimum VREF occurs at the lower temperature, the coefficient is positive.
4. The dynamic impedance is defined as:|Z
KA |+
VKA
I
K
When the device is operating with two external resistors, (see Figure xx), the total dynamic impedance of the circuit is given by:
|ZȀ|+V
I[|Z
KA |ǒ1)R1
R2Ǔ
PARAMETER MEASUREMENT INFORMATION
INPUT
Vref
VKA
IK
SL01177
Figure 3. Test Circuit for VKA = Vref
R1
R2
INPUT
Vref
VKA
Iref
IK
VKA +Vrefǒ1)R1
R2Ǔ)Iref R1
SL01178
Figure 4. Test Circuit for VKA > Vref
INPUT VKA
Ioff
SL01179
Figure 5. Test Circuit for IOFF
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 6
–50 –25 0 25 50 75 100 125
2600
2560
2500
2420
2400
Tamb – TEMPERATURE – (°C)
REFERENCE INPUT VOLTAGE – (mV)
SL01170
Vref = 2550mV
Vref = 2495mV
Vref = 2440mV
VKA = Vref
IK = 10mA
2440
2460
2480
2520
2540
2580
Vref –
Figure 6. Reference Input Voltage vs. Temperature
100
75
50
25
0
–25
–50
–75
–100 –2–10123
CATHODE VOLTAGE – (V)
CATHODE CURRENT – (mA)
SL01171
125
150 VKA = Vref
Tamb = 25°C
Figure 7. Cathode Current vs. Cathode Voltage
800
600
400
200
0
–200 –10123
V
KA – CATHODE VOLTAGE – (V)
CATHODE CURRENT – ( A)µ
VKA = Vref
Tamb = 25°C
SL01172
IK–
Imin
Figure 8. Cathode Current vs. Cathode Voltage
3.0
2.5
2.0
1.5
1.0
0.5
0–75 –50 –25 0 25 50 75 100 125
R1 = 10kΩ
R2 = ∞
IK = 10mA
Tamb – TEMPERATURE – (°C)
REFERENCE INPUT CURRENT – ( A)µ
SL01168
Iref –
Figure 9. Reference Input Current vs. Temperature
0
10
20
30
40
50
60
70
80
90
–75 –50 –25 0 25 50 75 100 125
VKA = 36V
Vref = 0V
Tamb – TEMPERATURE – (°C)
OFF-STATE CA THODE CURRENT – (nA)
SL01169
Ioff –
Figure 10. Off-State Cathode Current vs. Temperature
0
–0.1
–0.2
–0.3
–0.4
–0.5
–0.6
–0.7
–0.8
–0.9
–1–75 –50 –25 0 25 50 75 100 125
VKA = 3V TO 36V
Tamb – TEMPERATURE – (°C)
d(Vref)/d(Vka) – (mV/V)
SL01173
Figure 11. Ratio of Delta Reference Voltage to
Delta Cathode Voltage over Temperature
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 7
4
3
2
1
0
–1
–2
–3
–4 012345678910
t – TIME – (SECONDS)
SL01174
Vn – INPUT NOISE VOLTAGE – Vµ
VEE
160kΩ
0.1µF
820Ω
910Ω
16kΩ
VCC
TLE2027
AV = 10V/mV
500µF
1kΩ
19.1V
2000µF
TL431
(DUT)
16kΩ
1µF
33kΩ
1µF
VEE
VCC
TLE2027
AV = 2V/V
33kΩ
22µF
CRO
1MΩ
16Ω
Equivalent Input Noise Voltage Over a 10-Second Period
Test Circuit
Figure 12.
400
350
300
250
200
150
10010 100 1K 10K 100K
IK = 10mA
Tamb = 25°C
f–FREQUENCY–Hz
Vn – NOISE VOLTAGE – nV/ Hz
SL01180
√
Figure 13. Equivalent Input Noise Voltage vs. Frequency
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 8
TYPICAL CHARACTERISTICS
SL01182
Pulse Response
01234567
t – TIME – µs
7
6
5
4
3
2
1
0
INPUT AND OUTPUT VOLTAGE – V
Test Circuit
50Ω
OUTPUT
GND
220Ω
PULSE
GENERATOR
f = 100kHz
Figure 14. Pulse Response
100
90
80
70
60
50
40
30
20
10
0
0.001 0.01 0.1 1 10
CL – LOAD CAPACITANCE – (µF)
CATHODE CURRENT – (mA)
K
I
Tamb = 25°C
AV
KA = Vref
BV
KA = 5V
CV
KA = 10V
DV
KA = 15V
A
A
B
C
D
STABLE STABLE
UNSTABLE
VKA < 5
UNSTABLE
VKA < 10
UNSTABLE VKA < 15V
SL01176
–
UNSTABLE VKA
CL
150Ω
IK
VBATT
Test Circuit for Curve A
CL
150Ω
IK
VBATT
R1 = 10kΩ
R2
Test Circuit for Curves B, C, and D
Figure 15. Stability Boundary Conditions
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 9
IK
OUTPUT
GND
50Ω
1kΩ
Test Circuit for Reference Impedance
1K 10K 100K 1M 10M
0.1
1
10
100
f – FREQUENCY – Hz
|Z | – REFERENCE IMPEDANCE – Ω
KA
SL01175
IK = 10mA
Tamb = 25°C
Figure 16. Reference Impedance vs. Frequency
20
10
01K 10K 100K 1M 10M
FREQUENCY IN Hz
70
60
50
40
30
Av – VOLTAGE AMPLIFICATION – dB
IK = 10mA
Tamb = 25°C
SL01181
Test Circuit for Voltage Amplification
230Ω
IK
15kΩ
OUTPUT
GND
8.25kΩ
9µF
Figure 17. Small-Signal Voltage Amplification vs. Frequency
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 10
TYPICAL APPLICATIONS
R1
VOUT
R2
V+
VOUT +ǒ1)R1
R2ǓVref
SL01183
Figure 18. Shunt Regulator
VOUT
V+
VIN
VTH = Vref
VIN VOUT
< Vref V+
> Vref ≈2.0V
SL01184
Figure 19. Single-Supply Comparator with
T emperature-Compensated Threshold
R1
VOUT
R2
V+
VOUT +ǒ1)R1
R2ǓVref
SL01185
Figure 20. High Current Shunt Regulator
VOUT +ǒ1)R1
R2ǓVref
VOUT Min = Vref + Vbe
R1
VOUT
R2
V+
SL01186
Figure 21. Series Pass Regulator
IOUT +Vref
RCL
V+ IOUT
RCL
SL01187
Figure 22. Constant Current Source
V+ ISINK
RS
ISINK +Vref
RS
SL01189
Figure 23. Constant Current Sink
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 11
SO8: plastic small outline package; 8 leads; body width 3.9mm SOT96-1
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 12
DIP8: plastic dual in-line package; 8 leads (300 mil) SOT97-1
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 13
SOT54
1.6
4.2 max.
1
2
3
4.8
max. 2.54
0.66
0.56
5.2 max.
2.0 max. (1)
12.7 min.
0.40
min.
0.48
0.40
Dimensions in mm.
(1) Terminal dimensions within this zone are uncontrolled to allow for flow of plastic and terminal irregularities.
SL01191
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 14
TO-92 transistors on tape TO-92
P
A1
A
H2
P0
P2
F
F1F2D0
(p)
H1
H0
L
W2
W0W1
W
t
t1
T
∆h∆h
SL01192
Table 2. Tape specification (TO-92 leaded types)
SYMBOL
DIMENSION
SPECIFICATIONS
REMARKS
SYMBOL
DIMENSION
MIN. NOM. MAX. TOL. UNIT
REMARKS
A1Body width 4 – 4.8 – mm
ABody height 4.8 5.2 – mm
TBody thickness 3.5 3.9 – mm
PPitch of component – 12.7 – ±1 mm
P0Feed hole pitch – 12.7 – ±0.3 mm
Cumulative pitch error – – – ±0.1 mm Note 1
P2Feed hole center to component center – 6.35 – ±0.4 mm to be measured at bottom of clinch
FDistance between outer leads – 5.08 – +0.6/–0.2 mm
∆hComponent alignment – 0 1 – mm
WTape width – 18 – ±0.5 mm
W0Hold-down tape width – 6 – ±0.2 mm
W1Hole position – 9 – +0.7/–0.5 mm
W2Hold-down tape position – 0.5 – ±0.2 mm
H0Lead wire clinch height – 16.5 – ±0.5 mm
H1Component height – – 23.25 – mm
LLength of snipped leads – – 11 – mm
D0Feed hole diameter – 4 – ±0.2 mm
tTotal tape thickness – – 1.2 – mm
F1, F2Lead-to-lead distance – – – +0.4/–0.2 mm
H2Clinch height – – – – mm
(p) Pull-out force 6 – – – N
NOTE:
1. Measured over 20 devices.
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 15
Tape splicing
Splice the carrier tape on the back and/or front so that the feed hole
pitch (P0) is maintained.
Bulk packing
In addition to TO-92 on tape, TO-92 can also be delivered in bulk.
Products are packed in boxes in foil and plastic bags with 1,000
pieces to a bag and 5 bags to a box.
SPC F (Note 1)SPC T (Note 1)
ÉÉÉÉÉÉÉ
CARRIER STRIP
ADHESIVE TAPE
ROUNDED
SIDE
FEED
ROUNDED SIDE OF TRANSISTOR AND ADHESIVE TAPE VISIBLE
ADHESIVE TAPE FLAT SIDE
FEED
FLAT SIDE OF TRANSISTOR AND ADHESIVE TAPE VISIBLE
VREF
PIN
CATHODE
PIN
LABEL CARRIER STRIP LABEL
SL01193
Figure 24. TO-92 Reel Styles
SPC A (Note 1)
ÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉ
CARRIER STRIP
ADHESIVE TAPE ON TOP SIDE
LABEL
FLAT SIDE
FLAT SIDE OF TRANSISTOR
AND ADHESIVE TAPE VISIBLE
In Ammo Pack, the parts are put on the tape
the same as in SPC T. However, depending
on which end of the Ammo Pack is opened,
the VREF OR Cathode pin may come first. If
opened from the end marked with a “+”, the
Cathode comes first.
SL01194
Figure 25. TO-92 Ammo Pack Styles
NOTE:
1. Order SPC F, T or A depending on what is required.
Philips Semiconductors Product specification
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
1997 Feb 25 16
Philips Semiconductors and Philips Electronics North America Corporation reserve the right to make changes, without notice, in the products,
including circuits, standard cells, and/or software, described or contained herein in order to improve design and/or performance. Philips
Semiconductors assumes no responsibility or liability for the use of any of these products, conveys no license or title under any patent, copyright,
or mask work right to these products, and makes no representations or warranties that these products are free from patent, copyright, or mask
work right infringement, unless otherwise specified. Applications that are described herein for any of these products are for illustrative purposes
only. Philips Semiconductors makes no representation or warranty that such applications will be suitable for the specified use without further testing
or modification.
LIFE SUPPORT APPLICATIONS
Philips Semiconductors and Philips Electronics North America Corporation Products are not designed for use in life support appl iances, devices,
or systems where malfunction of a Philips Semiconductors and Philips Electronics North America Corporation Product can reasonably be expected
to result in a personal injury. Philips Semiconductors and Philips Electronics North America Corporation customers using or selling Philips
Semiconductors and Philips Electronics North America Corporation Products for use in such applications do so at their own risk and agree to fully
indemnify Philips Semiconductors and Philips Electronics North America Corporation for any damages resulting from such improper use or sale.
This data sheet contains preliminary data, and supplementary data will be published at a later date. Philips
Semiconductors reserves the right to make changes at any time without notice in order to improve design
and supply the best possible product.
Philips Semiconductors
811 East Arques Avenue
P.O. Box 3409
Sunnyvale, California 94088–3409
Telephone 800-234-7381
DEFINITIONS
Data Sheet Identification Product Status Definition
Objective Specification
Preliminary Specification
Product Specification
Formative or in Design
Preproduction Product
Full Production
This data sheet contains the design target or goal specifications for product development. Specifications
may change in any manner without notice.
This data sheet contains Final Specifications. Philips Semiconductors reserves the right to make changes
at any time without notice, in order to improve design and supply the best possible product.
Copyright Philips Electronics North America Corporation 1997
All rights reserved. Printed in U.S.A.
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