CYStech Electronics Corp.
Spec. No. : C502A3
Issued Date : 2003.03.26
Revised Date : 2005.06.29
Page No. : 1/6
TL431A3 CYStek Product Specification
Adjustable Precision Shunt Regulators
TL431XA3
Description
The TL431 series are three-terminal adjustable regulators with guaranteed
thermal stability over applicable temperature ranges. The output voltage
may be set to any value between VREF (approximately 2.495 volts) and 36 volts with two external resistors.
These devices have a typical dynamic output impedance of 0.2Ω. Active output circuitry provides a very
sharp turn-on characteristic, making these devices excellent replacement for zener diodes in many
applications.
Features
• Programmable output voltage
• Temperature coefficient is 50ppm/°C typical
• Temperature compensated for operation over
• full temperature range
• Low output noise voltage
• Fast turn on response
• Pb-free package
Classification
Rank A B C
VREF 2.495±0.5% 2.495±1% 2.495±2%
Absolute Maximum Ratings
(Operating temperature range applies unless otherwise specified)
Characteristics Symbol Value Unit
Cathode Voltage VKA 37 V
Cathode Current Range (Continuous) IK -100~+150 mA
Reference Input Current Range IREF 0.05~+10 mA
Power Dissipation PD 770 mW
Operating Temperature Range Topr 0~+70 °C
Storage Temperature Range Tstg -65~+150 °C
TO-92
CYStech Electronics Corp.
Spec. No. : C502A3
Issued Date : 2003.03.26
Revised Date : 2005.06.29
Page No. : 2/6
TL431A3 CYStek Product Specification
Functional Block Diagram & Symbol
Test Circuits
Electrical Characteristics ( Ta=25°C unless otherwise specified )
Characteristics Symbol Test Conditions Min Typ Max Unit
TL431A 2.445 2.495 2.545
TL431B 2.470 2.495 2.520
Reference Input Voltage
TL431C
VREF V
KA=VREF, IK=10mA
2.480 2.495 2.510
V
Deviation of Reference Input Voltage
Over-Temperature VREF(dev)
VKA=VREF, IK=10mA
Tmin≤Ta≤Tmax - 4 17 mV
IK=10mA,
∆VKA=10V-VREF - -1.4 -2.7 mV
Ratio of Change in Reference Input
Voltage to the Change in Cathode
Voltage
∆VREF /
∆VKA IK=10mA,
∆KKA=36V-10V - -1.0 -2.0 V
Reference Input Current IREF IK=10mA, R1=10kΩ,
R2=∞ - 2 4 µA
Deviation of Reference Input Current
Over Full Temperature Range IREF(dev)
IK=10mA, R1=10kΩ,
R2=∞, Ta=Full Range - 0.4 1.2 µA
Minimum Cathode Current for
Regulation IK(min) V
KA=VREF - 0.4 1.0 mA
Off-State Cathode Current IK(off) V
KA=36V, VREF=0 - 0.1 1.0 µA
Dynamic impedance ZKA VKA=VREF, f≤1.0KHz
IK=1 to 100mA - 0.2 0.5
Ω
Functional Block Diagram : Symbol :
Cathode
Reference
Anode
Cathode
VREF
+
-
Reference
Anode
IN VZ
II
IREF
VREF
IZ
R1
Fig1. Test Circuit for VZ=VREF
II
VZ
IN
IREF
IZ
R2
VREF
Fig 2. Test Circuit for VZ>VREF
Note : VZ=VREF(1+R1/R2)+IREFxR1
IN VZ
Fig3. Test Circuit for Off-State
Current
CYStech Electronics Corp.
Spec. No. : C502A3
Issued Date : 2003.03.26
Revised Date : 2005.06.29
Page No. : 3/6
TL431A3 CYStek Product Specification
Characteristic Curves
CATHODE CURRENT vs
CATHODE VOLTAGE
-100
-75
-50
-25
0
25
50
75
100
125
150
-1.5 -1 -0.5 0 0.5 1 1.5 2 2.5
VAK - CATHODE VOLTAGE (V)
IK - COTHODE CURRENT (mA)
CATHODE CURRENT vs
CATHODE VOLTAGE
-200
-100
0
100
200
300
400
500
600
700
800
-1 -0.5 0 0.5 1 1.5 2 2.5 3
VAK - CATHODE VOLTAGE (V)
IK - COTHODE CURRENT (uA)
REFERENCE INPUT VOLTAGE
vs AMBIENT TEMPERATURE
2.45
2.452
2.454
2.456
2.458
2.46
2.462
2.464
0 25 50 75 100 125
AMBIENT TEMPERATURE(℃ )
Vref - REFERENCE INPUT
VOLTAGE (mV)
REFERENCE INPUT CURRENT
vs AMBIENT TEMPERATURE
0
50
100
150
200
250
300
350
0 25 50 75 100 125
AMBIENT TEMPERATURE(℃ )
Vref - REFERENCE INPUT
CURRENT (nA)
CATHODE VOLTAGE vs REFERENCE
INPUT VOLTAGE
-30
-25
-20
-15
-10
-5
0
0 5 10 15 20 25 30 35 40
VKA - CATHODE VOLTAGE (V)
ΔVref - REFERENCE INPUT
VOLTAGE (mV)
DYNAMIC IMPEDANCE vs FREQUENCE
0.1
1
10
100
1 10 100 1000
f - FREQUENCE (KHz)
ZKA - DYNAMIC IMPEDANCE (Ω
)
CYStech Electronics Corp.
Spec. No. : C502A3
Issued Date : 2003.03.26
Revised Date : 2005.06.29
Page No. : 4/6
TL431A3 CYStek Product Specification
OPEN-LOOP VOLTAGE GAIN
vs FREQUENCY
0
10
20
30
40
1 10 100 1000
F - FREQUENCY (KHz)
OPEN-LOOP VOLTAGE GAI
N
(dB)
CYStech Electronics Corp.
Spec. No. : C502A3
Issued Date : 2003.03.26
Revised Date : 2005.06.29
Page No. : 5/6
TL431A3 CYStek Product Specification
TO-92 Taping Outline
Millimeters
DIM Item Min. Max.
A Component body height 4.33 4.83
D Tape Feed Diameter 3.80 4.20
D1 Lead Diameter 0.36 0.53
D2 Component Body Diameter 4.33 4.83
F1,F2 Component Lead Pitch 2.40 2.90
F1,F2 F1-F2 - ±0.3
H Height Of Seating Plane 15.50 16.50
H1 Feed Hole Location 8.50 9.50
H2 Front To Rear Deflection - 1
H2A Deflection Left Or Right - 1
H3 Component Height - 27
H4 Feed Hole To Bottom Of Component - 21
L Lead Length After Component Removal - 11
L1 Lead Wire Enclosure 2.50 -
P Feed Hole Pitch 12.50 12.90
P1 Center Of Seating Plane Location 5.95 6.75
P2 4 Feed Hole Pitch 50.30 51.30
T Over All Tape Thickness - 0.55
T1 Total Taped Package Thickness - 1.42
T2 Carrier Tape Thickness 0.36 0.68
W Tape Width 17.50 19.00
W1 Adhesive Tape Width 5.00 7.00
- 20 pcs Pitch 253 255
H2AH2A
H2H2 D2
A
H
W
W1
H3
H4
H1
L1
L
P2
P
P1
F1F2 D1 D
T2
T
T1
CYStech Electronics Corp.
Spec. No. : C502A3
Issued Date : 2003.03.26
Revised Date : 2005.06.29
Page No. : 6/6
TL431A3 CYStek Product Specification
TO-92 Dimension
*: Typical
Inches Millimeters Inches Millimeters
DIM Min. Max. Min. Max.
DIM Min. Max. Min. Max.
A 0.1704 0.1902 4.33 4.83 G 0.0142 0.0220 0.36 0.56
B 0.1704 0.1902 4.33 4.83 H - *0.1000 - *2.54
C 0.5000 - 12.70 - I - *0.0500 - *1.27
D 0.0142 0.0220 0.36 0.56 α1 - *5° - *5°
E - *0.0500 - *1.27 α2 - *2° - *2°
F 0.1323 0.1480 3.36 3.76 α3 - *2° - *2°
Notes: 1.Controlling dimension: millimeters.
2.Maximum lead thickness includes lead finish thickness, and minimum lead thickness is the minimum thickness of base material.
3.If there is any question with packing specification or packing method, please contact your local CYStek sales office.
Material:
• Lead: 42 Alloy ; solder plating
• Mold Compound: Epoxy resin family, flammability solid burning class: UL94V-0
Important Notice:
• All rights are reserved. Reproduction in whole or in part is prohibited without the prior written approval of CYStek.
• CYStek reserves the right to make changes to its products without notice.
• CYStek semiconductor products are not warranted to be suitable for use in Life-Support Applications, or systems.
• CYStek assumes no liability for any consequence of customer product design, infringement of patents, or application assistance.
431
Marking:
31
A
D
B
C
Iα1
E
F
α2
α3
G
H
2
Style: Pin 1.Reference 2.Anode 3.Cathode
3-Lead TO-92 Plastic Package
CYStek Packa
g
e Code:
A
3
