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AS431 Datasheet, PDF (1/19 Pages) Alpha Industries – Precision Adjustable Shunt Regulator
A Product Line of
Diodes Incorporated
AS431
ADJUSTABLE PRECISION SHUNT REGULATORS
Description
The AS431 is a three-terminal adjustable shunt regulator with
guaranteed thermal stability over a full operation range. It features
sharp turn-on characteristics, low temperature coefficient and low
output impedance, which make it ideal substitute for Zener diode in
applications such as switching power supply, charger and other
adjustable regulators.
The output voltage of AS431 can be set to any value between VREF
(2.5V) and the corresponding maximum cathode voltage (36V).
The AS431 precision reference is offered in two voltage tolerance:
0.5% and 1.0%.
This IC is available in 4 packages: TO-92 (bulk or ammo packing),
SOT-23, SOT-23-5 and SOT-89.
Features
 Programmable Precise Output Voltage from 2.5V to 36V
 High Stability under Capacitive Load
 Low Temperature Deviation: 4.5mV Typical
 Low Equivalent Full-range Temperature Coefficient with
20PPM/°C Typical
 Sink Current Capacity from 1mA to 100mA
 Low Output Noise
 Wide Operating Range of -40 to +125°C
 Lead-Free Packages: SOT-23, SOT-23-5, TO-92, SOT-89
 Totally Lead-Free; RoHS Compliant (Notes 1 & 2)
 Lead-Free Packages, Available in “Green” Molding Compound:
SOT-23, SOT-23-5, TO-92, SOT-89
 Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
 Halogen and Antimony Free. “Green” Device (Note 3)
Applications
 Charger
 Voltage Adapter
 Switching Power Supply
 Graphic Card
 Precision Voltage Reference
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. See http://www.diodes.com/quality/lead_free.html for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green"
and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
Pin Assignments
N Package
(SOT-23)
R Package
(SOT-89 Option 1)
R Package
(SOT-89 Option 2)
K Package
(SOT-23-5)
1
2
3
REF ANODE CATHODE
Z Package
(TO-92 (Bulk Packing))
3 CATHODE
2 ANODE
1 REF
Note:
4. * Pin 2 is attached to substrate and must be connected to ANODE or open.
AS431
Document number: DS36599 Rev. 3 - 2
1 of 19
www.diodes.com
1
2
3
REF ANODE CATHODE
Z Package
(TO-92 (Ammo Packing))
October 2013
© Diodes Incorporated