MB3773 Datasheet, PDF (22/29 Pages) Fujitsu Component Limited. – Power Supply Monitor with Watch-Dog Timer

MB3773
EXAMPLE 10: Circuit for Monitoring Multiple Microprocessor
VCC ( = 5 V)
FF1
S
D1 Q1
CK1 Q1
R
FF2
S
D2 Q2
CK2 Q2
R
FF3
S
D3 Q3
CK3 Q3
R
R2
R1
*
*
*
RESET
RESET
RESET
RESET
CK
RESET
CK
RESET
CK
GND
GND
GND
*: Microprocessor
18
27
CT ^{3 6}
45
MB3773
Notes : •
connects from FF1 and FF2 outputs Q1 and Q2 to the NOR input.
• Depending on timing, these connections may not be necessary.
• Example : R1 = R2 = 2.2 kΩ
CT = 0.1 µF
Figure 1
CK1
Q1
CK2
Q2
CK3
Q3
NOR
Output
Figure 2
22