MB3773 Fujitsu, MB3773 Datasheet - Page 14

• Manufacturer Part Number: MB3773
• Description: Power Supply Monitor with Watch-Dog Timer
• Manufacturer: Fujitsu

14
MB3773
V
CC
(5V)
• Comp. 1 and Comp. 2 are used to monitor for overvoltage while the MB3773 is used to monitor for low
• Use V
voltage.
Detection voltages V
V
For the formulas for finding hysterisis width and detection voltage, see section 4.
2L
/V
EXAMPLE 6 : Montitoring Low voltage and Overvoltage Monitoring (with hysterisis)
C
2H
CC
T
at the time of overvoltage are approximately 6.0V/6.1V.
(=5V) to power the comparators (Comp. 1 and Comp. 2) in the external circuit shown above.
1
1
2
3
4
/V
MB3773
1H
at the time of low voltage areappoximately 4.2V/4.3V. Detection voltages
1.2k
8
7
6
5
5.6k
R
R
1
2
4.7k
R
5
30k
R
+
_
3
R
180k
Comp. 1
4
RESET
Diode
0
Comp. 2
+
_
Example
R
20k
V
6
1L
V
1H
: Comp. 1, Comp. 2
: MB4204, MB47393
RESET
RESET
CK
V
2L
GND
V
2H
Logic circuit
V
CC