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■ Adjustable output voltage: 2.5 to 36V
■ Sink current capability: 1 to 100mA
■ Typical output impedance: 0.22Ω
■ 1% and 2% voltage precision
Description
The TL431 is a programmable shunt voltage
reference with guaranteed temperature stability
over the entire temperature range of operation.
TL431
Programmable Voltage Reference
Z
TO92
(Plastic Package)
The output voltage may be set to any value
between 2.5V and 36V with two external resistors.
The TL431 operates with a wide current range
(Plastic Micropackage)
D
SO-8
from 1 to 100mA with a typical dynamic
impedance of 0.22Ω.
Order Codes
Part Number
TL431CD/CDT
TL431ACD/ACDT 431AC
TL431CZ/CZT/CZ-AP
TL431ACZ/ACZT/ACZ-AP TL431AC
TL431ID/IDT
TL431AID/AIDT 431AI
TL431IZ/IZT/IZ-AP
TL431AIZ/AIZT/AIZ-AP TL431AI
Temperature
Range
0, +70°C
-40, + 105°C
Package Packing Marking
SO-8
TO92
SO-8
TO92
Tube or Tape & Reel
431C
TL431C
431I
TL431I
TL431IYD/IYDT
SO-8 (automotive grade level)
TL431AIYD/AIYDT 431AIY
November 2005 1/13
431IY
Rev 2
www.st.com
13
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Pin Diagrams TL431
1 Pin Diagrams
Figure 1. TO92 pin connections (top view)
Cathode
Anode
123
Figure 2. SO-8 pin connections (top view)
8765
1234
Reference
1 - Cathode
2 - Anode
3 - Anode
4 - N.C.
5 - N.C.
6 - Anode
7 - Anode
8 - Reference
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TL431 Absolute Maximum Ratings
2 Absolute Maximum Ratings
Table 1. Key parameters and their absolute maximum ratings
Symbol Parameter Value Unit
V
T
1. Pd is calculated with T
Cathode to Anode Voltage 37 V
KA
I
Continuous Cathode Current Range -100 to +150 mA
k
I
Reference Input Current Range -0.05 to +10 mA
ref
Power Dissipation
P
d
TO92
SO-8 batwing
Storage Temperature Range -65 to +150 °C
stg
R
= 200°C/W for TO92 package
thja
R
= 130°C/W for SO-8 batwing package
thja
(1)
= +25°C, Tj = +150°C and
amb
625
960
mW
Table 2. Operating conditions
Symbol Parameter Value Unit
V
T
Cathode to Anode Voltage
KA
I
Cathode Current 1 to 100 mA
k
Operating Free-air Temperature Range
oper
TL431C/AC
TL431I/AI
to 36
V
ref
0 to +70
-40 to +105
V
°C
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Electrical Characteristics TL431
3 Electrical Characteristics
Tabl e 3 . T
= 25°C (unless otherwise specified)
amb
Symbol Parameter
Reference Input Voltage
V
ref
= V
V
KA
T
min
, Ik = 10 mA, T
ref
≤T
amb
≤ T
amb
max
Reference Input Voltage Deviation Over Temperature
ref
Range
VKA = Vref, Ik = 10 mA, T
min
∆V
(1)
Ratio of Change in Reference Input Voltage to Change
∆Vref
------------
∆Vka
in Cathode to Anode Voltage
Ik = 10mA - ∆V
∆V
= 36V to 10V
KA
= 10V to Vref
KA
Reference Input Current
Ik = 10mA, R1 = 10kΩ, R2 = ∞
I
ref
T
T
amb
min
= 25°C
≤T
amb
≤T
max
Reference Input Current Deviation Over Temperature
∆I
⏐ZKA⏐
1.∆V
Range
I
min
I
∆
ref
off
V
Ik = 10mA, R1 = 10kΩ, R2 =∞
T
≤T
amb
≤ T
max
min
Minimum Cathode Current for Regulation
= V
V
KA
ref
Off-State Cathode Current 2.6 1000 2.6 1000 nA
Dynamic Impedance
VKA = V
is defined as the difference between the maximum and minimum values obtained over the full temperature range.
ref
= V
ref
ref max.
, ∆ Ik = 1 to100mA, f ≤1kHZ
ref
- V
ref min.
(2)
= 25°C
≤T
amb
≤ T
max
TL431C TL431AC
Min. Typ. Max. Min. Typ. Max.
2.44
2.423
2.495 2.55
2.567
2.47
2.453
2.495 2.52
2.537
317 315
-1.4-1-2.7
-2
1.8 4
5.2
-1.4-1-2.7
-2
1.8 4
5.2
0.4 1.2 0.4 1.2
0.5 1 0.5 0.6
0.22 0.5 0.22 0.5
Unit
V
mV
mV/V
µA
µA
mA
Ω
V
ref max.
V
ref min.
T1
2. The dynamic Impedance is definied as |ZKA|
∆VKA
=
------ ---------- -
∆IK
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T2
Temperature