Product data
Supersedes data of 1997 Feb 25
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2002 Jan 22
INTEGRATED CIRCUITS
Philips Semiconductors Product data
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2
2002 Jan 22 853–1927 27590
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 2.5 V) and 36 V with two
external resistors (see Figure 4). These devices have a typical
output impedance of 0.2 Ω. 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: 30 ppm/°C
•0.2 Ω typical output impedance
•Sink current capability: 1 mA to 100 mA
•Low output noise
•Adjustable output voltage: VREF to 36 V
PIN CONFIGURATIONS
1
2
3
45
6
7
8CATHODE
ANODE
ANODE
NC
REF
ANODE
ANODE
NC
D Package
SOT96-1
1
2
3
45
6
7
8CATHODE
NC
NC
NC
REF
NC
ANODE
NC
N Package
SOT97-1
D5 Package
SOT680-1
SL01581
TOP VIEW
TOP VIEW
1
2
34
5NC
NC
CATHODE
ANODE
VREF
TOP VIEW
Figure 1. Pin configuration.
ORDERING INFORMATION
DESCRIPTION TEMPERATURE
RANGE INDUSTRY STANDARD
PART NUMBER ORDER CODE DWG #
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
5-pin plastic small outline package (SO5) 0 °C to +70 °C TL431ACD5 SOT680-1
5-pin plastic small outline package (SO5) –40 °C to +85 °C TL431AID5 SOT680-1
5-pin plastic small outline package (SO5) 0 °C to +70 °C TL431CD5 SOT680-1
5-pin plastic small outline package (SO5) –40 °C to +85 °C TL431ID5 SOT680-1
NOTE:
1. SYMBOL INFORMATION: Parts will be marked with product name including temperature and electrical grade desginators, but not the
package identifier .
Philips Semiconductors Product data
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2002 Jan 22 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 1.6 mm (1/16 in.) from case for 10 sec: D5, D or P pkgs 260 °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
D5 5.1 mW/°C637 mW 408 mW 332 mW
D5.8 mW/°C725 mW 464 mW 429 mW
P8.0 mW/°C1000 mW 640 mW 520 mW
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 data
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2002 Jan 22 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 = 10 mA 2470 2495 2520 2440 2495 2550 mV
VREF(dev) Deviation of reference input
voltage over full
temperature range2Fig. 3 VKA = VREF, IK = 10 mA;
Tamb = full range14 15 4 17 mV
DVREF Ratio of change in
reference input volta
g
e to
Fig 4
I=10mA
∆VKA = 10 V – VREF –1.4 –2.7 –1.4 –2.7
mV/V
REF
DVKA
g
the change in cathode
voltage
Fig
.
4
I
K =
10
mA
∆VKA = 36 V – 10 V –1 –2 –1 –2
mV/V
IREF Reference input current Fig. 4 IK = 10 mA, R1 = 10 kΩ, R2 = ∞2 4 2 4 µA
IREF(dev) Deviation of reference input
current over full
temperature range2Fig. 4 IK = 10 mA, R1 = 10 kΩ, R2 = ∞,
Tamb = full range10.8 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 = 36 V, VREF = 0 0.1 0.5 0.1 1µA
| ZKA | Dynamic impedance3Fig. 3 VKA = VREF, IK = 1 mA to 100 mA;
f ≤ 1 kHz 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 = 10 mA 2470 2495 2520 2440 2495 2550 mV
VREF(dev) Deviation of reference input
voltage over full
temperature range2Fig. 3 VKA = VREF, IK = 10 mA,
Tamb = full range15 25 5 30 mV
DVREF Ratio of change in
reference input volta
g
e to
Fig 4
I=10mA
∆VKA = 10 V – VREF –1.4 –2.7 –1.4 –2.7
mV/V
REF
DVKA
g
the change in cathode
voltage
Fig
.
4
I
K =
10
mA
∆VKA = 36 V – 10 V –1 –2 –1 –2
mV/V
IREF Reference input current Fig. 4 IK = 10 mA, R1 = 10 kΩ, R2 = ∞2 4 2 4 µA
IREF(dev) Deviation of reference input
current over full
temperature range2Fig. 4 IK = 10 mA, R1 = 10 kΩ, R2 = ∞,
Tamb = full range10.8 2.5 0.8 2.5 µA
IMIN Minimum cathode current
for regulation Fig. 3 VKA = VREF 0.4 0.7 0.4 1µA
IOFF Off-state cathode current Fig. 5 VKA = 36 V, VREF = 0 0.1 0.5 0.1 1µA
| ZKA | Dynamic impedance3Fig. 3 VKA = VREF, IK = 1 mA to 100 mA,
f ≤ 1 kHz 0.2 0.5 0.2 0.5 Ω
NOTES:
1. 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.
2. 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:
|aVREF |ǒppm
degCǓ+ǒVREF(dev)
VREF at 25oCǓ@106
DTamb VREF(dev)
Max VREF
Min VREF
∆Tamb
where ∆Tamb is the rated operating free-air temperature range of the device.
Philips Semiconductors Product data
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2002 Jan 22 5
αVREF can be positive or negative depending on whether minimum VREF of maximum VREF, respectively, occurs at the lower temperature.
Example: Max VREF = 2496 mV at 30 °C, Min VREF = 2492 mV at 0 °C, VREF = 2495 mV at 25 °C, DTA = 70 °C for TL431C.
|aVREF |+ǒ4mV
2495mVǓ@106
70oC+23ppmńoC
Because minimum VREF occurs at the lower temperature, the coefficient is positive.
3. The dynamic impedance is defined as:|Z
KA |+
DVKA
DI
K
When the device is operating with two external resistors, (see Figure 4), the total dynamic impedance of the circuit is given by:
|ZȀ|+DV
DI[|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 data
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2002 Jan 22 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
VKA – 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 CATHODE 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 data
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2002 Jan 22 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 data
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2002 Jan 22 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 data
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2002 Jan 22 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 data
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2002 Jan 22 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 data
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2002 Jan 22 11
SO8: plastic small outline package; 8 leads; body width 3.9 mm SOT96-1
Philips Semiconductors Product data
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2002 Jan 22 12
DIP8: plastic dual in-line package; 8 leads (300 mil) SOT97-1
Philips Semiconductors Product data
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2002 Jan 22 13
SO5: plastic small outline package; 5 leads; body width 1.6 mm SOT680-1
Philips Semiconductors Product data
TL431C, TL431AC, TL431I,
TL431AI, LM431AC
Adjustable precision shunt regulators
2002 Jan 22 14
Definitions
Short-form specification — The data in a short-form specification is extracted from a full data sheet with the same type number and title. For
detailed information see the relevant data sheet or data handbook.
Limiting values definition — Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 60134). Stress above one
or more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or
at any other conditions above those given in the Characteristics sections of the specification is not implied. Exposure to limiting values for extended
periods may af fect device reliability.
Application information — Applications that are described herein for any of these products are for illustrative purposes only. Philips
Semiconductors make no representation or warranty that such applications will be suitable for the specified use without further testing or
modification.
Disclaimers
Life support — These products are not designed for use in life support appliances, devices or systems where malfunction of these products can
reasonably be expected to result in personal injury . Philips Semiconductors customers using or selling these products for use in such applications
do so at their own risk and agree to fully indemnify Philips Semiconductors for any damages resulting from such application.
Right to make changes — Philips Semiconductors reserves 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.
Contact information
For additional information please visit
http://www.semiconductors.philips.com. Fax: +31 40 27 24825
For sales offices addresses send e-mail to:
sales.addresses@www.semiconductors.philips.com.
Koninklijke Philips Electronics N.V. 2002
All rights reserved. Printed in U.S.A.
Date of release: 01-02
Document order number: 9397 750 09375
Data sheet status[1]
Objective data
Preliminary data
Product data
Product
status[2]
Development
Qualification
Production
Definitions
This data sheet contains data from the objective specification for product development.
Philips Semiconductors reserves the right to change the specification in any manner without notice.
This data sheet contains data from the preliminary specification. Supplementary data will be
published at a later date. Philips Semiconductors reserves the right to change the specification
without notice, in order to improve the design and supply the best possible product.
This data sheet contains data from the product specification. Philips Semiconductors reserves the
right to make changes at any time in order to improve the design, manufacturing and supply.
Changes will be communicated according to the Customer Product/Process Change Notification
(CPCN) procedure SNW-SQ-650A.
Data sheet status
[1] Please consult the most recently issued data sheet before initiating or completing a design.
[2] The product status of the device(s) described in this data sheet may have changed since this data sheet was published. The latest information is available on the Internet at URL
http://www.semiconductors.philips.com.
