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■ADJ U STABL E 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.
The output voltage may be set to any value
between 2.5V and 36V with t wo external resistors.
The TL431 operates with a wide current range
from 1 to 100mA with a typical dynamic
impedance of 0.22Ω.
ORDER CODE
Z = TO92 Plastic package - also available in Bulk (Z), Tape & Reel (ZT)
and Ammo Pack (AP)
D = Small Outline Pac kage (SO) - also available in Tape & Reel (DT)
PIN CONNECTIONS (top view)
Part
Number Temperature
Range Package
ZD
TL431C/AC 0° C, +70°C ••
TL431I/AI -40°C, +105°C ••
Z
TO92
(Plastic Pack age)
D
SO8
(Batwing Plastic Micropackage)
TO92
(Top view) SO8
(Top view)
Cathode
Anode
Reference
123
8765
1234
1- Cathode
2- Anode
3- Anode.
4- N.C.
5- N.C.
6- Anode
7- Anode.
8- Reference
2-
TL431
PROGRAMMAB LE VOLTAG E REFERENCE
March 2002
TL431
2/10
ABSOLUTE MAXIMUM RATINGS
OPERATING CONDITIONS
ELECTRICAL CHARACTERISTICS
Tamb = 25°C (unless otherwise specified)
1) ∆Vref is defined as the difference between the maximum and minimum values obtained over the full temperature range.
∆Vref = Vref max. - Vref min.
2) The dynamic Impedance is definied as ZKA =
Symbol Parameter Value Unit
VKA Cathode to Anode Voltage 37 V
IkContinuous Cathode Current Range -100 to +150 mA
Iref Reference Input Current Range -0.05 to +10 mA
pdPower Dissipation 1) TO92
SO8 batwing 625
960 mW
Tstg Storage Temperature Range -65 to +150 °C
1. Pd is calculated with Tamb = +25°C, Tj = +150°C and Rthja = 200°C/W for TO92 package
= 130°C/W for SO8 batwing package
Symbol Parameter Value Unit
VKA Cathode to Anode Voltage Vref to 36 V
IkCathode Current 1 to 100 mA
Toper Operating Free-air Temperature Range TL431C/AC
TL431I/AI 0 to +70
-40 to +105 °C
Symbol Parameter TL431C TL431AC Unit
Min. Typ. Max. Min. Typ. Max.
Vref
Reference Input Voltage
VKA = Vref , Ik = 10 mA Tamb = 25°C
Tmin ≤Tamb ≤ Tmax
2.44
2.423 2.495 2.55
2.567 2.47
2.453 2.495 2.52
2.537 V
∆Vref
Reference Input Voltage Deviation Over-
Temperature Range - note 1
VKA = Vref, Ik = 10 mA,Tmin ≤Tamb ≤ Tmax 3 17 3 15 mV
Ratio of Change in Reference Input
Voltage to Change in Cathode to Anode
Voltage - (figure 2)
Ik = 10mA ∆VKA = 10V to Vref
∆VKA = 36V to 10V -1.4
-1 -2.7
-2 -1.4
-1 -2.7
-2 mV/V
Iref
Reference Input Current
Ik = 10mA, R1 = 10kΩ, R2 = ∞
Tamb = 25°C
Tmin ≤Tamb ≤Tmax
1.8 4
5.2 1.8 4
5.2 µA
∆Iref
Reference Input Current Deviation
Over Temperature Range
Ik = 10mA, R1 = 10kΩ, R2 =∞
Tmin ≤Tamb ≤ Tmax 0.4 1.2 0.4 1.2 µA
Imin Minimum Cathode Current for Regulation
VKA = Vref 0.5 1 0.5 0.6 mA
Ioff Off-State Cathode Current 2.6 1000 2.6 1000 nA
ZKA Dynamic Impedance - note 2
VKA = Vref ,∆ Ik = 1 to100mA, f ≤1kHZ 0.22 0.5 0.22 0.5 Ω
∆Vref
∆Vka
------------
T1 T2 Temperature
V
ref max.
V
ref min.
∆VKA
∆IK
-----------------
TL431
3/10
ELECTRICAL CHARACTERISTICS
Tamb = 25°C (unless otherwise specified)
1) ∆Vref is defined as the difference between the maximum and minimum values obtained over the full temperature range.
∆Vref = Vref max. - Vref min.
2) The dynamic Impedance is definied as ZKA =
Symbol Parameter TL431I TL431AI Unit
Min. Typ. Max. Min. Typ. Max.
Vref Reference Input Voltage
VKA = Vref , Ik = 10 mA Tamb = 25°C
Tmin ≤Tamb ≤ Tmax
2.44
2.41 2.495 2.55
2.58 2.47
2.44 2.495 2.52
2.55 V
∆Vref
Reference Input Voltage Deviation Over-
Temperature Range - note 1
VKA = Vref , Ik =10 mA,Tmin≤Tamb≤ Tmax 7 30 7 30 mV
Ratio of Change in Reference Input
Voltage to Change in Cathode to Anode
Voltage
Ik = 10mA ∆VKA = 10V to Vref
∆VKA = 36V to 10V -1.4
-1 -2.7
-2 -1.4
-1 -2.7
-2 mV/V
Iref
Reference Input Current
Ik = 10mA, R1 = 10kΩ, R2 = ∞
Tamb = 25°C
Tmin ≤Tamb ≤Tmax
1.8 4
6.5 1.8 4
6.5 µA
∆Iref
Reference Input Current Deviation
Over Temperature Range
Ik = 10mA, R1 = 10kΩ, R2 =∞
Tmin ≤Tamb ≤ Tmax 0.8 2.5 0.8 1.2 µA
Imin Minimum Cathode Current for Regulation
VKA = Vref 0.5 1 0.5 0.7 mA
Ioff Off-State Cathode Current 2.6 1000 2.6 1000 nA
ZKA Dynamic Impedance note 2
VKA = Vref ,∆ Ik = 1 to100mA, f ≤1kHZ 0.22 0.5 0.22 0.5 Ω
∆Vref
∆Vka
------------
T1 T2 Temperature
V
ref max.
V
ref min.
∆VKA
∆IK
-----------------
TL431
4/10
Fi gure 1 : Test Circuit for VKA = VREF
Fi gure 3 : Test Circuit for IOFF
Fi gure 5 : Blo ck diag ram of TL1431
Fi gure 2 : Test Circuit for VKA > VREF
Fi gure 4 : Tes t Circuit for Phase Margi n and
Volt age Ga in
Figure 6 : Test Circuit for Response time
Input
VKA
VREF
IK=10mA
Output
R
VKA=36V
IOFF
Vref
Cathode
Anode
+
-
Vref
Vref
Cathode
Anode
+
-
Vref
VKA = VREF + R1 x IREF 1 R1
R2
--------+()
Input
VKA
VREF
IK
R1
R2
IREF
ROutput
Input VREF
IK=10mA
Output
10µF
10µF
15kΩ8.25kΩ
IK=1mA
Output
0 mA
1 mA
TL431
5/10
Refe renc e voltage vs Temp eratu re
Referenc e vol tage vs cathode current
Off-state ca thode curr ent vs te mpe ratu re
Referenc e voltage vs catho de current
Reference current vs temperature
Ratio of change in VREF to change in VKA vs
Temperature
-40 -20 0 20 40 60 80 100
2.44
2.46
2.48
2.50
2.52
2.54
V
KA
= V
REF
I
K
= 10 mA
Cathode voltage V
KA
(V)
Temperature (
°
C)
-10123
-2
-1
0
1
2
T
AMB
= +25
°
C
Cathode current I
KA
(mA)
Cathode voltage V
KA
(V)
-40 -20 0 20 40 60 80 100
0.0
0.5
1.0
1.5
2.0
V
KA
= 36 V
V
REF
= 0 V
Off-state current I
OFF
(
µ
A)
Temperature (
°
C)
-10123
-50
-25
0
25
50
75
100
T
AMB
=+25
°
C
Cathode current I
KA
(mA)
Cathode voltage V
KA
(V)
−40 −20 0 20 40 60 80 100
0.0
0.5
1.0
1.5
2.0
I
K
=10 mA
R
1
=10k
Ω
R2= +
∝
Reference current I
REF
(
µ
A)
Temperature °C
-40 -20 0 20 40 60 80 100
-2.0
-1.5
-1.0
-0.5
0.0
IK = 10 mA
∆VREF / ∆VKA (mV / V)
Temperature (°C)
TL431
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Static impe dance RKA vs Temperature
Gai n & Phase vs Frequency
Ma xi m um P ower di ss i pat i on
Mi nimum op erati ng current vs temperatur e
Stability behaviour with capacitive loads
Pulse resp on se for IK=1m A
-40 -20 0 20 40 60 80 100
0.20
0.22
0.24
0.26
0.28
0.30
VKA=VREF
TAMB=+25°C
Static impedance RKA (Ω)
Temperature (°C)
1 10 100 1000 10000
-40
-20
0
20
40
60
-200
-150
-100
-50
0
50
100
150
200
Gain (dB)
Frequency (kHz)
I
K
=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)
-40 -20 0 20 40 60 80 100
0.0
0.2
0.4
0.6
V
KA
= V
REF
Minimum cathode current I
MIN
(mA)
Temperature (
°
C)
1E-10 1E-9 1E-8 1E-7 1E-6 1E-5
0
20
40
60
80
100
Instable
Area
VKA=24 V
VKA=12 V
VKA=5 V
VKA=VREF
Cathode current (mA)
Capacitive load (Farad)
0246810
0
2
4
6
VKA=VREF
TAMB=+25°C
Output
Input
Input and Output voltage (V)
Time (µs)
TL431
7/10
PACKAGE MECHANICAL DATA
8 PINS - BATWI NG PLASTIC MICROPACKA GE (SO )
Dim. Millimeters Inches
Min. Typ. Max. Min. Typ. Max.
A 1.75 0.069
a1 0.1 0.25 0.004 0.010
a2 1.65 0.065
a3 0.65 0.85 0.026 0.033
b 0.35 0.48 0.014 0.019
b1 0.19 0.25 0.007 0.010
C 0.25 0.5 0.010 0.020
c1 45° (typ.)
D 4.8 5.0 0.189 0.197
E 5.8 6.2 0.228 0.244
e 1.27 0.050
e3 3.81 0.150
F 3.8 4.0 0.150 0.157
L 0.4 1.27 0.016 0.050
M 0.6 0.024
S 8° (max.)
b
e3
A
a2
s
L
C
E
c1
a3
b1
a1
DM
85
14
F
TL431
8/10
PACKAGE MECHANICAL DATA
3 PINS - PLASTIC PACKAGE TO92 (TAPE & REEL)
Dim. Millimeters Inches
Min Typ. Max. Min. Typ. Max.
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
∆h -1 0 1 -0.039 0 0.039
∆P -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
H 20 0.787
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
A1
P
P
A
TH
H1
H
L1
d
I1
H0
W2W0
W1
W
D0
F1 F2
P2
P0
TL431
9/10
PACKAGE MECHANICAL DATA
3 PINS - PLASTIC PACKAGE TO92 (TAPE AMMO PACK)
Dim. Millimeters Inches
Min Typ. Max. Min. Typ. Max.
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
∆h -1 0 1 -0.039 0 0.039
∆P -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
H 20 0.787
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
A1
P
P
A
TH
H1
H
L1
d
I1
H0
W2W0
W1
W
D0
F1 F2
P2
P0
TL431
10/10
PACKAGE MECHANICAL DATA
3 PINS - PLASTIC PACKAGE TO92 (BULK)
Dim. Millimeters Inches
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
K 12.7 0.5
O2 0.407 0.5 0.508 0.016 0.0197 0.02
a 0.35 0.0138
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