Renesas 4514 - Manual (Page 65)

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HARDWARE
4513/4514 Group User’s Manual
VOLTAGE DROP DETECTION CIRCUIT
The built-in voltage drop detection circuit is designed to detect a
drop in voltage and to reset the microcomputer if the supply voltage
drops below a set value.
Fig. 37 Voltage drop detection circuit operation waveform
Fig. 36 Voltage drop detection reset circuit
Voltage drop detection circuit
Internal reset signal RESET pin
Watchdog timer output
WEF
Note: The output structure of RESET pin is N-channel open-drain.
V DD
V RST (detection voltage)
Voltage drop detection
circuit output
The microcomputer starts
operation after f(X
IN ) is counted
16892 to 16895 times.
RESET pin
Notes 1: Pull-up RESET pin externally.
2: Refer to the voltage drop detection circuit in the electrical characteristics
for the rating value of V RST (detection voltage).
FUNCTION BLOCK OPERATIONS