MB3793-42PNF-G Datasheet, PDF (17/23 Pages) Fujitsu Component Limited. – POWER-VOLTAGE MONITORING IC WITH WATCHDOG TIMER

s STANDARD CONNECTION
VCC
MB3793-42
CTW
CTP
5
VCC
RESET ¹
2 CTW
MB3793
3 CTP
CK1 8
INH GND
6
4
CK2 7
RESET VCC
CK
Micro-
processor 1
GND
RESET VCC
CK _Micro-
processor 2
GND
Equation of time-setting capacitances (CTP and CTW) and set time
tPR (ms) ≈ A × CTP (µF)
tWD (ms) ≈ B × CTW (µF) + C × CTP (µF)
However, when CTP/CTW ≤ 10,
tWD (ms) ≈ B × CTW (µF)
tWR (ms) ≈ D × CTP (µF)
Value of A, B, C and D
A
B
C
1300
1500
3
D
Remark
100
(Example) When CTP = 0.1 µF and CTW = 0.01 µF,
tPR ≈ 130 [ms]
tWD ≈ 15 [ms]
tWR ≈ 10 [ms]
17