APL431
Adjustable Precision Shunt Regulator
Features
•
•
•
•
•
•
•
•
Precise Reference Voltage to 2.500V
Guaranteed 0.5%, 1% or 2% Reference
Voltage Tolerance
Sink Current Capability, 1mA to 100mA
Quick Turn-on
Adjustable Output Voltage, V
O
= V
ref
to 20V
Low Operational Cathode Current, 250µA
Typical
0.1Ω Typical Output Impedance
SOT-23, SOT-23-5, SOT-89, SO-8, TO-92
and TO-92S Packages
General Description
The APL431 is a 3-terminal adjustable voltage refer-
ence with specified thermal stability over applicable
commercial temperature ranges. Output voltage may
be set to any value between V
ref
(2.5 V) and 20 V with
two external resistors (see Figure 2). When used
with an photocoupler, the APL431 is an ideal voltage
reference in isolated feedback circuits for 2.5V to 12V
switching-mode power supplies. This device has a
typical output impedance of 0.1Ω. Active output cir-
cuitry provides a very sharp turn-on characteristic,
making the APL431 excellent replacements for ze-
ner diodes in many applications, including on-board
regulation and adjustable power supplies.
NC
ANODE
3
1
2
NC
5
1
2
4
3
Applications
•
•
•
Linear Regulators
Adjustable Power Supply
Switching Power Supply
1
REF
CATHODE
R EF AN O D E C ATH O D E
SOT-23 (Top View)
SOT-23-5 (Top View)
CATHODE
ANODE
2
3
1
2
3
4
8
7
6
5
REF
ANODE
ANODE
NC
Symbol
REF
Anode
Cathode
REF
ANODE CATHODE
ANODE
NC
SOT-89 (Top View)
SO-8 (Top View)
3
CATHODE
Functional Diagram
C athode
3
CATHODE
2
ANODE
2
ANODE
R EF
+
_
1
REF
1
REF
V
ref
TO-92 (Top View)
Anode
TO-92S (Top View)
ANPEC reserves the right to make changes to improve reliability or manufacturability without notice, and advise
customers to obtain the latest version of relevant information to verify before placing orders.
Copyright
ANPEC Electronics Corp.
Rev. C.1 - Jun., 2003
1
www.anpec.com.tw
ANPEC [ ANPEC ELECTRONICS COROPRATION ]
