October 2003
rev 1.0
ASM809, ASM810
Block Diagram
SOT23
GND
1
Pin Diagram
V
CC
ASM809
(ASM810)
3
V
CC
+
-
+
-
RESET Generator
4.63V
4.38V
4.00V
3.08V
2.93V
2.63V
RESET
(RESET)
(RESET) RESET
2
ASM809
(ASM810)
GND
Pin Description
Pin #
ASM809
1
2
ASM810
-
-
Pin
Name
GND
RESET
Ground.
RESET is asserted LOW if V
CC
falls below V
TH
and remains LOW for T
RST
after V
CC
exceeds the
threshold.
RESET is asserted HIGH if V
CC
falls below V
TH
and remains HIGH for T
RST
after V
CC
exceeds the
threshold.
Power supply input voltage (3.0V, 3.3V, 5.0V).
Function
-
3
2
-
RESET
V
CC
Detailed Description
A
proper
reset
input
enables
a
microprocessor
/
V
CC
5V
0V
V
TH
microcontroller to start in a known state. ASM809/810 assert
reset to prevent code execution errors during power-up,
power-down and brown-out conditions.
RESET
Reset Timing
The reset signal is asserted- LOW for the ASM809 and HIGH
for the ASM810- when the V
CC
supply voltage falls below the
threshold trip voltage and remains asserted for 140ms
minimum after the V
CC
has risen above the threshold.
RESET
5V
0V
5V
0V
T
RST
ASM809
ASM810
Figure 1: Reset TIming Diagram
3 Pin Microcontroller Power Supply Supervisor
Notice: The information in this document is subject to change without notice
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ALSC [ ALLIANCE SEMICONDUCTOR CORPORATION ]
