AP431/AP431A
Adjustable Precision Shunt Regulator
Application Examples
V
IN
V
IN
R
CL
R
R1A
R1B
V
IN
I
OUT
ON
R2A
R2B
OFF
+
LED on when Low Limit
＜
V
IN
＜
High Limit
Low Limit
≈
V
REF
(1+R1B/R2B)
High Limit
≈
V
REF
(1+R1A/R2A)
V
IN
Delay = RC x ln(
)
V
IN
-V
REF
I
OUT
= V
REF
/ R
CL
Fig.4 Voltage Monitor
Fig.5 Delay Timer
Fig.6 Current Limiter or Current Source
V
IN
I
OUT
V
IN
V
OUT
V
IN
PUSE
R1
V
OUT
R1
R
S
R2
R2
I
OUT
= V
REF
/ R
S
V
OUT
= (1 + R1/R2) x V
REF
L
IMIT
(1 + R1/R2) x V
REF
Fig.7 Constant-Current Sink
Fig.8 Higher-Current Shunt Regulator
Fig.9 Crow Bar
V
IN
R1A
R1B
Output ON when
Low Limint < V
IN
< High Limit
+
R2A
R2B
V
BE
Low Limit
High Limit
V
REF
(1 + R1B/R2B) +V
BE
V
REF
(1 + R1A/R2A)
Fig.10 Over-Voltage / Under-Voltage Protection Circuit
Anachip Corp.
www.anachip.com.tw
9/17
Rev.1.0 May.7, 2004
ANACHIP [ ANACHIP CORP ]
