October 2003
rev 1.0
Monitoring Voltages Other Than V
CC
The ASM706/708 can monitor voltages other than V
CC
using
the Power Fail circuitry. If a resistive divider is connected from
the voltage to be monitored to the PFI input, the PFO will go
LOW if the voltage at PFI goes below 1.25V reference. Should
hysteresis
be
desired,
connect
a
resistor
(equal
to
approximately 10 times the sum of the two resistors in the
divider) between the PFI and PFO pins. A capacitor between
PFI and GND will reduce circuit sensitivity to input high
frequency noise. If it is desired to assert a reset in addition to
the PFO flag, this may be achieved by connecting the PFO
output to MR.
R
2
R
1
V
IN
ASM706 P/ R/ S/ T/ J
ASM708 R/ S/ T/ J
+5V
V
CC
MR
PFI
ASM70X
PFO
GND
RESET
To
µP
Absolute Maximum Ratings
Parameter
Pin Terminal Voltage with Respect to Ground
V
CC
All other inputs
Input Current at V
CC
and GND
Output Current: All outputs
Rate of Rise at V
CC
Plastic DIP Power Dissipation
(Derate 9mW/°C above 70°C)
SO Power Dissipation
(Derate 5.9mW/°C above 70°C)
MicroSO POwer Disspation
(Derate 4.1mW/°C above 70°C)
Operating Temperature Range
ASM706xE, ASM708xE
ASM706xC, ASM708xC
Storage Temperature Range
Lead Temperature Soldering (10sec)
Figure 4: Monitoring +5V and an additional supply V
IN
Min
Max
Unit
-0.3
-0.3
6.0
V
CC
+ 0.3
20
20
100
700
470
330
V
V
mA
mA
V/µs
mV
mW‘
mW
-40
0
-65
+85
70
160
300
°C
°C
°C
°C
Note: These are stress ratings only and functional operation is noy implied. Exposure to absolute maximum ratings for pro-
longed time periods may affect device reliability.
3/3.3/4.0 V µP Supervisor Circuits
Notice: The information in this document is subject to change without notice
7 of 16
ALSC [ ALLIANCE SEMICONDUCTOR CORPORATION ]
