Features
TL1431
Programmable voltage reference
■ Adjustable output voltage: V
■ Sink current capability: 1 to 100 mA
■ Typical output impedance: 0.22 Ω
■ 0.4% and 0.25% voltage precision
REF
to 36 V
Description
The TL1431 is a programmable shunt voltage
reference with guaranteed temperature stability
over the entire operating temperature range.
The output voltage may be set to any value
between 2.5 V and 36 V with two external
resistors.
The TL1431 operates with a wide current range
from 1 to 100 mA with a typical dynamic
impedance of 0.2 Ω.
Z
TO92
(Plastic package)
D
SO-8
(Batwing plastic micropackage)
March 2008 Rev 4 1/16
www.st.com
16
Schematic diagrams TL1431
1 Schematic diagrams
Figure 1. TO92 pin connections (top view)
Cathode
Figure 2. SO-8 pin connections (top view)
Anode
123
8765
Reference
1 - Cathode
2 - Anode
3 - Anode
4 - N.C.
5 - N.C.
6 - Anode
7 - Anode
8 - Reference
1234
Figure 3. TL1431 block diagram
Cathode
Cathode
Vref
Vref
Vref
Vref
2/16
+
+
-
-
Anode
Anode
TL1431 Absolute maximum ratings and operating conditions
2 Absolute maximum ratings and operating conditions
Table 1. Absolute maximum ratings
Symbol Parameter Value Unit
V
T
ESD
1. Calculated with Tj=+150°C and T
2. Human body model: A 100 pF capacitor is charged to the specified voltage, then discharged through a
3. Machine model: A 200pF capacitor is charged to the specified voltage, then discharged directly between
4. Charged device model: all pins and the package are charged together to the specified voltage and then
Table 2. Operating conditions
Cathode to anode voltage 37 V
KA
I
Continuous cathode current range -100 to +150 mA
k
Reference input current range -0.05 to +10 mA
I
ref
Junction temperature +150 °C
T
j
Power dissipation
P
d
TO92
SO-8 batwing
Storage temperature range -65 to +150 °C
stg
HBM: human body model
MM: machine model
CDM: charged device model
1.5 kΩ resistor between two pins of the device. This is done for all couples of connected pin combinations
while the other pins are floating.
two pins of the device with no external series resistor (internal resistor < 5 Ω). This is done for all couples of
connected pin combinations while the other pins are floating.
discharged directly to the ground through only one pin. This is done for all pins.
(1)
(2)
(3)
=+25°C with relative R
amb
(4)
depending on the package.
thja
625
960
2000
200
1500
mW
V
Symbol Parameter Value Unit
V
Cathode to anode voltage V
KA
I
Cathode current 1 to 100 mA
k
to 36 V
ref
Operating free-air temperature range
T
oper
TL1431C/AC
TL1431I/AI
-20 to +70
-40 to +105
°C
Thermal resistance junction to ambient
R
thja
SO-8 batwing
TO92
130
200
°C/W
3/16
Electrical characteristics TL1431
3 Electrical characteristics
Table 3. T
= 25°C (unless otherwise specified)
amb
TL1431C TL1431AC
Symbol Parameter
Min. Typ. Max. Min. Typ. Max.
Reference input voltage - see Figure 4
ref
ref
ΔT
= V
V
KA
Reference input voltage deviation ov er
temperature range
VKA = V
Temperature coefficient of reference input
voltage
VKA = V
, Ik = 10 mA
ref
, Ik = 10 mA, T
ref
(2)
, Ik = 10 mA, T
ref
(1)
- see Figure 4
≤ T
min
≤T
min
Ratio of change in reference input voltage to
change in cathode to anode voltage - see
Figure 5
= 10mA - ΔVKA = 36V to 3V
I
k
amb
amb
≤ T
≤ T
2.490 2.500 2.510 2.493 2.500 2.507 V
320 320mV
max
±13 ±90 ±13 ±90 ppm/°C
max
-2 -1.1 -2 -1.1 mV/V
ΔV
ΔVref
--------------- -
ΔVref
--------------- -
ΔVka
V
Reference input current
I
ref
= 10mA, R1 = 10kΩ, R2 = ∞
I
k
T
≤ T
amb
≤ T
max
min
1.5 2.5
3
1.5 2.5
Reference input current deviation over
ΔI
I
⏐ Z
1. See Reference input voltage deviation over temperature range in Section 4: Parameter definitions on page 9.
2. See Temperature coefficient of reference input voltage in Section 4: Parameter definitions on page 9.
3. See Dynamic impedance in Section 4: Parameter definitions on page 9.
temperature range
ref
= 10mA, R1 = 10kΩ, R2 =∞, T
I
k
min
≤ T
amb
≤ T
max
Minimum cathode current for regulation - Figure 4
min
I
off
KA
⏐
= V
V
KA
ref
Off-state cathode current - see Figure 6 180 500 180 500 nA
Dynamic impedance
VKA = V
, ΔIk = 1 to100mA, f ≤ 1kHz
ref
(3)
0.2 1.2 0.2 1.2 µA
0.5 1 0.5 0.6 mA
0.20.5 0.20.5 Ω
Unit
µA
3
4/16
TL1431 Electrical characteristics
Table 4. T
= 25°C (unless otherwise specified)
amb
TL1431I TL1431AI
Symbol Parameter
Min. Typ. Max. Min. Typ. Max.
Reference input voltage - see Figure 4
ref
VKA = V
Reference input voltage deviation over
temperature range
ref
V
KA
Temperature coefficient of reference input
voltage
VKA = V
ref
= V
, Ik = 10 mA, T
ref
(2)
, Ik = 10 mA, T
ref
, Ik = 10 mA
(1)
- see Figure 4
≤ T
min
≤ T
min
Ratio of change in reference input voltage to
change in cathode to anode voltage - see
Figure 5
= 10mA - ΔVKA = 36V to 3V
I
k
amb
amb
≤ T
≤ T
2.490 2.500 2.510 2.493 2.500 2.507 V
730 730mV
max
±22 ±100 ±22 ±100 ppm/°C
max
-2 -1.1 -2 -1.1 mV/V
ΔV
ΔVref
--------------- -
ΔVref
--------------- -
ΔVka
V
ΔT
Reference input current
I
ref
= 10mA, R1 = 10kΩ, R2 = ∞
I
k
≤ T
T
min
amb
≤ T
max
1.5 2.5
3
1.5 2.5
Reference input current deviation over
ΔI
temperature range
ref
= 10mA, R1 = 10kΩ, R2 =∞, T
I
k
min
≤ T
amb
≤ T
max
0.5 1 0.8 1.2 µA
Minimum cathode current for regulation - see
I
I
⏐ Z
1. See Reference input voltage deviation over temperature range in Section 4: Parameter definitions on page 9.
2. See Temperature coefficient of reference input voltage in Section 4: Parameter definitions on page 9.
3. See Dynamic impedance in Section 4: Parameter definitions on page 9.
Figure 4
min
off
KA
⏐
= V
V
KA
ref
Off-state cathode current - see Figure 6 180 500 180 500 nA
Dynamic impedance
VKA = V
, ΔIk= 1 to100mA, f ≤ 1kHz
ref
(3)
0.5 1 0.5 0.7 mA
0.20.5 0.20.5 Ω
Unit
µA
3
5/16
Electrical characteristics TL1431
Figure 4. Test circuit for VKA = V
Input
V
Figure 6. Test circuit for I
R
IK=10mA
REF
OFF
VKA=36V
I
OFF
REF
Output
V
KA
Figure 5. Test circuit for VKA = V
Input
V
KA
R1
R2
= V
REF
R
I
REF
V
REF
R1
+ R1 x I
------- -+()
R2
REF
I
K
1
REF
Output
V
KA
Figure 7. Test circuit for phase margin and
voltage gain
10μF
15kΩ
IK=10mA
10μF
8.25kΩ
Input
V
REF
Figure 8. Test circuit for response time Figure 9. Reference voltage vs. temperature
2.500
2.498
2.496
2.494
2.492
Reference voltage (V)
2.490
2.488
2.486
-40 -20 0 20 40 60 80 100 120
Temperature (°C)
IK=10 mA
V
See figure 1
KA=VREF
=2.5 V
0 mA
IK=1mA
1 mA
Output
Output
6/16
TL1431 Electrical characteristics
Figure 10. Reference voltage vs. cathode
Reference voltage (V)
current
3
2
VKA=V
1
0
-1
-40 -20 0 20 40 60 80 100
Cathode current (mA)
REF
See figure 1
Figure 11. Reference voltage vs. cathode
current
3.0
2.5
2.0
VKA=V
1.5
1.0
Reference voltage (V)
0.5
0.0
0.0 0.2 0.4 0.6 0.8 1.0
Cathode current (mA)
REF
See figure 1
Figure 12. Reference current vs. temperature Figure 13. Off-state cathode current vs.
temperature
2.0
1.5
0.10
0.08
VKA = 36V
See figure 3
1.0
(µA)
REF
I
IK=10 mA
0.5
0.0
-40 -20 0 20 40 60 80 100 120
Temperature (°C)
V
KA=VREF
See figure 1
Figure 14. Ratio of change in V
in V
vs. temperature
KA
0.0
-0.5
(mV / V)
KA
-1.0
/ ΔV
REF
ΔV
-1.5
-2.0
-40 -20 0 20 40 60 80 100 120
Temperature (°C)
to change
REF
IK=10 mA
V
KA=VREF
See figure 2
0.06
(µA)
OFF
I
0.04
0.02
0.00
-40 -20 0 20 40 60 80 100 120
Figure 15. Drift of R
0.00
-0.01
(Ω)
-0.02
KA
Δ R
-0.03
-0.04
-40 -20 0 20 40 60 80 100 120
Temperature(°C)
vs. temperature
KA
IK=10 mA
V
= 2.5V
KA=VREF
see figure 1
Temperature (°C)
7/16
Electrical characteristics TL1431
1 10 100 1000 10000
-40
-20
0
20
40
60
-200
-150
-100
-50
0
50
100
150
200
Gain (dB)
Frequency (kHz)
IK=10 mA
See figure 4
Phase
Gain
Phase (
°
)
10 20 30
0
20
40
60
80
100
T
AMB
= +25°C
Safe
Area
SO8
Batwing
TO92
Cathode current (mA)
Cathode voltage (V)
Figure 16. Maximum operating current vs.
temperature
0.52
0.50
0.48
IK=I
0.46
(mA)
MIN
I
MIN
VKA=V
REF
See figure 1
0.44
0.42
0.40
-40 -20 0 20 40 60 80 100 120
Temperature (°C)
Figure 18. Stability behavior with capacitive
loads
100
VKA=V
VKA=5V
VKA=12V
VKA=24V
REF
Instable
Area
Stable
Area
80
Stable
60
Area
40
Cathode current (mA)
20
Figure 17. Gain and phase vs. frequency
Figure 19. Maximum power dissipation
0
1E-10 1E-9 1E-8 1E-7 1E-6 1E-5
Figure 20. Pulse response for I
6
4
Voltage (V)
2
0
012345
8/16
T
AMB
See figure 6
Capacitive Load (F)
=+25°C
Time (µs)
= 1 mA
K
Current step: 1 mA
Output voltage
TL1431 Parameter definitions
4 Parameter definitions
Reference input voltage deviation over temperature range
Δ
V
is defined as the diff e rence bet we en th e maxim um an d minim um values obtained over
ref
the full temperature range.
Δ
V
= V
ref
ref max.
Figure 21. Reference input voltage deviation over temperature range
V
V
ref max.
ref min.
- V
T1
ref min.
T2
Temperature
Temperature coefficient of reference input voltage
The temperature coefficient is defined as the slopes (positive and negative) of the voltage
versus temperature limits within which the reference is guaranteed.
Figure 22. Temperature coefficient of reference input voltage
-n ppm/°C
Max
+n ppm/°C
2.5V
min
Temperature
25°C
Dynamic impedance
ΔV
KA
The dynamic impedance is defined as | Z
KA
--------------- -
|
=
ΔI
K
9/16
Package information TL1431
5 Package information
In order to meet environmental requ irements, ST offers these devices in ECOPACK®
packages. These packages have a lead-free second level interconnect. The category of
second level interconnect is marked on the package and on the inner box label, in
compliance with JEDEC Standard JESD97. The maximum ratings related t o soldering
conditions are also marked on the inner box label. ECOPACK is an ST trademark.
ECOPACK specifications are available at: www.st.com
.
10/16
TL1431 Package information
5.1 SO-8 batwing package information
Figure 23. SO-8 batwing package mechanical drawing
Table 5. SO-8 batwing package mechanical data
Dimensions
Ref.
Min. Typ. Max. Min. Typ. Max.
A1.750.069
A1 0.10 0.25 0.004 0.010
A2 1.25 0.049
b 0.28 0.48 0.011 0.019
c 0.17 0.23 0.007 0.010
D 4.804.905.000.1890.1930.197
E 5.806.006.200.2280.2360.244
E1 3.80 3.90 4.00 0.150 0.154 0.157
e 1.27 0.050
h 0.25 0.50 0.010 0.020
L 0.40 1.27 0.016 0.050
k1°8°1°8°
ccc 0.10 0.004
Millimeters Inches
11/16
Package information TL1431
5.2 TO92 (ammopack and tape and reel) package information
Figure 24. TO-92 ammopack and tape and reel package mechanical drawing
A1
P
P
A
d
H
H1
L1
D0
P2
Table 6. TO-92 ammopack and tape and reel package mechanical data
I1
F1
F2
P0
W2
H0
W0
Millimeters Inches
Dim.
Min Typ. Max. Min. Typ. Max.
T
H
W1
W
AL 5.0 0.197
A 5.0 0.197
T 4.0 0.157
d 0.45 0.018
I1 2.5 0.098
P 11.7 12.7 13.7 0.461 0.500 0.539
PO 12.4 12.7 13 0.488 0.500 0.512
P2 5.95 6.35 6.75 0.234 0.250 0.266
F1/F2 2.4 2.5 2.8 0.094 0.098 0.110
Δh -1 0 1 -0.039 0 0.039
ΔP -1 0 1 -0.039 0 0.039
W 17.5 18.0 19.0 0.689 0.709 0.748
W0 5.7 6 6.3 0.224 0.236 0.248
W1 8.5 9 9.75 0.335 0.354 0.384
W2 0.5 0.020
H200.787
H0 15.5 16 16.5 0.610 0.630 0.650
H1 25 0.984
DO 3.8 4.0 4.2 0.150 0.157 0.165
L1 11 0.433
12/16
TL1431 Package information
5.3 TO92 (bulk) package information
Figure 25. TO-92 bulk package mechanical drawing
Table 7. TO-92 bulk package mechanical data
Millimeters Inches
Dim.
Min Typ. Max. Min. Typ. Max.
L 1.27 0.05
B 3.2 3.7 4.2 0.126 0.1457 0.1654
O1 4.45 5.00 5.2 0.1752 0.1969 0 .2047
C 4.58 5.03 5.33 0.1803 0.198 0.2098
K12.7 0.5
O2 0.407 0.5 0.508 0.016 0.0197 0.02
a 0.35 0.0138
13/16
Ordering information TL1431
6 Ordering information
Table 8. Order codes
Order code
TL1431CD
TL1431CDT
TL1431ACD
TL1431ACDT
TL1431CZ
TL1431CZT
TL1431CZ-AP
TL1431ACZ
TL1431ACZT
TL1431ACZ-AP
TL1431ID
TL1431IDT
TL1431AID
TL1431AIDT
TL1431IZ
TL1431ZT
TL1431IZ-AP
TL1431AIZ
TL1431AIZT
TL1431AIZ-AP
TL1431IYD
TL1431IYDT
(1)
(1)
Temperature
range
-20°C, +70°C
-40°C, + 105°C
Package Packing Marking
SO-8
Tube or
tape and reel
Bulk or
TO92
Tape or
Ammopack
SO-8
Tube or
tape and reel
Bulk or
TO92
Tape or
Ammopack
SO-8
(Automotive grade)
Tube or
tape and reel
1431C
1431AC
TL1431C
TL1431AC
1431I
1431AI
TL1431I
TL1431AI
1431IY
1. Qualification and characterization according to AEC Q100 and Q003 or equivalent, advanced screening
according to AEC Q001 and Q 002 or equivalent are on-going.
14/16
TL1431 Revision history
7 Revision history
Table 9. Document revision history
Date Revision Changes
01-Mar-2002 1 Initial release.
01-Nov-2005 2
25-Apr-2007 3
11-Mar-2008 4
PPAP references inserted in the datasheet see
on page 14.
Minimum value for temperature range updated in
conditions
Minimum values added and maximum values deleted for
parameter in
Package information for TO92 tape and reel updated, see
Package information
Format update.
Corrected SO-8 package mechanical data.
Corrected footnote for automotive grade order codes in order code
table.
Corrected packing information for TO92 devices in order code table.
.
Table 4 in Section 3: Electrical characteristics.
.
Table 8: Order codes
Table 2: Operating
ΔVref
--------------- -
ΔVka
Section 5:
15/16
TL1431
Please Read Carefully:
Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the
right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any
time, without notice.
All ST products are sold pursuant to ST’s terms and conditions of sale.
Purchasers are solely res ponsibl e fo r the c hoic e, se lecti on an d use o f the S T prod ucts and s ervi ces d escr ibed he rein , and ST as sumes no
liability whatsoever relati ng to the choice, selection or use o f the ST products and services described herein.
No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted under this document. If any part of this
document refers to any third pa rty p ro duc ts or se rv ices it sh all n ot be deem ed a lice ns e gr ant by ST fo r t he use of su ch thi r d party products
or services, or any intellectua l property c ontained the rein or consi dered as a warr anty coverin g the use in any manner whats oever of suc h
third party products or servi ces or any intellectual property contained therein.
UNLESS OTHERWISE SET FORTH IN ST’S TERMS AND CONDITIONS OF SALE ST DISCLAIMS ANY EXPRESS OR IMPLIED
WARRANTY WITH RESPECT TO THE USE AND/OR SALE OF ST PRODUCTS INCLUDING WITHOUT LIMITATION IMPLIED
WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICUL AR PURPOS E (AND THEIR EQUIVALE NTS UNDER THE LAWS
OF ANY JURISDICTION), OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT.
UNLESS EXPRESSLY APPROVED IN WRITING BY AN AUTHORIZED ST REPRESENTATIVE, ST PRODUCTS ARE NOT
RECOMMENDED, AUTHORIZED OR WARRANTED FOR USE IN MILITARY, AIR CRAFT, SPACE, LIFE SAVING, OR LIFE SUSTAINING
APPLICATIONS, NOR IN PRODUCTS OR SYSTEMS WHERE FAILURE OR MALFUNCTION MAY RESULT IN PERSONAL INJ URY,
DEATH, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE. ST PRODUCTS WHICH ARE NOT SPECIFIED AS "AUTOMOTIVE
GRADE" MAY ONLY BE USED IN AUTOMOTIVE APPLICATIONS AT USER’S OWN RISK.
Resale of ST products with provisions different from the statements and/or technical features set forth in this document shall immediately void
any warranty granted by ST fo r the ST pro duct or serv ice describe d herein and shall not cr eate or exten d in any manne r whatsoever , any
liability of ST.
ST and the ST logo are trademarks or registered trademarks of ST in various countries.
Information in this document su persedes and replaces all information previously supplied.
The ST logo is a registered trademark of STMicroelectronics. All other names are the property of their respective owners.
© 2008 STMicroelectronics - All rights reserved
STMicroelectronics group of compan ie s
Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - I taly - Japan -
Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America
www.st.com
16/16
Loading...