Hitachi RAF-25FX8 Mode D'emploi page 118

6-2. Reset Circuit
MAIN P.W.B.
12V
R284
0V
0V
The reset circuit initializes the microcomputer program when Power is "ON" from "OFF"
Low voltage at pin
48
Fig. 6-7 shows the reset circuit and Fig. 6-8 shows waveform at each point when power is turned on and
off.
When power is turned on, 12V line and 5V line voltages rise and 12V line voltage reaches 10.9V an
reset voltage input to pin
Reset voltage will be hold "Hi" until the 12V line voltage drops to 9.90V even though the power shuts
down.
12
10.9V
6
0
12
6
0
D208
R287
2
3
IC5(1/2)
0V
R288
0V
resets the microcomputer, and HI activates the microcomputer
of microcomputer is set to Hi.
48
Reset voltage
5V
8
0V
-
1
R252
+
Fig. 6-7
12V line
5V line
Reset voltage
12V line
5V line
Fig. 6-8
– 136 –
Microcomputer
56
RESET OUT.
48
RESET
0V
Time
9.9V
Time