ASM802LAEPA ALSC [Alliance Semiconductor Corporation], ASM802LAEPA Datasheet - Page 2

• Manufacturer Part Number: ASM802LAEPA
• Description: UP Power Supply Supervisor With Battery Backup Switch
• Manufacturer: ALSC [Alliance Semiconductor Corporation]

October 2003
rev 1.0
Pin Configuration
Pin Description
ASM690A /
ASM802L /
ASM802M
ASM692A
1
2
3
4
5
6
7
8
-
Pin Number
ASM805L
µP Power Supply Supervisor With Battery Backup Switch
1
2
3
4
5
6
7
8
-
Notice: The information in this document is subject to change without notice
RESET
RESET
Name
V
V
GND
PFO
WDI
V
PFI
BATT
OUT
CC
V
GND
V
OUT
PFI
CC
Voltage supply for RAM. When V
V
output will be connected to the backup supply at V
higher) through the MOS switch to provide continuous power to the CMOS RAM.
+5V power supply input.
Ground
Power failure monitor input. PFI is connected to the internal power fail comparator
which is referenced to 1.25V. The power fail output (PFO) is active LOW but
remains HIGH if PFI is above 1.25V. If this feature is unused, the PFI pin should be
connected to GND or V
Power-fail output. PFO is active LOW whenever the PFI pin is less than 1.25V.
Watchdog input. The WDI input monitors microprocessor activity. An internal timer
is reset with each transition of the WDI input. If the WDI is held HIGH or LOW for
longer than the watchdog timeout period, typically 1.6 seconds, RESET (or RESET)
is asserted for the reset pulse width time, t
Active-LOW reset output. When triggered by V
or by watchdog timer timeout, RESET (or RESET) pulses low for the reset pulse
width t
(4.65V in ASM690A / ASM802L and 4.4V in the ASM692A / ASM802L) and
remains low for 200ms after V
Active-HIGH reset output. The inverse of RESET.
Auxiliary power or backup-battery input. V
function is not used. The input has about 40mV of hysteresis to prevent rapid tog-
gling between V
Plastic/CerDip/SO
CC
1
4
2
3
through a P-Channel MOS device. If V
RS
(ASM805L)
ASM690A
ASM692A
ASM802L
ASM802M
, typically 200ms. It will remain low if V
CC
and V
5
8
6
7
OUT
V
RESET (RESET)
WDI
PFO
BATT
BATT
.
.
CC
CC
rises above the reset threshold.
is above the reset threshold, V
Function
BATT
RS
CC
, of 140ms, minimum.
falls below the reset threshold, this
CC
should be connected to GND if the
CC
falling below the reset threshold
BATT
is below the reset threshold
ASM690A / 692A
ASM802L / 802M
(or V
CC
, whichever is
ASM805L
OUT
connects to
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