Hitachi RAM-60QH4 Manuel De Service page 92

7. Peripheral circuits of microcomputer
• Fig. 7-1 shows the microcomputer and its peripheral circuits.
Table 7-1, the basic operations of each circuit block and Fig.7-2, the system configuration.
SPM
terminal
−
DC current
Detection resistor
R24
0V
＋
−
〜
Table 7-1
Circuit block
Peak current cut off circuit
Overload external judgment
circuit
Voltage amplifier circuit
Reset circuit
＋
C224
− 5V
0V
5V
To drive circuit
0V
Is
D104 R110
R108
C031
0V 0V
Fig. 7-1 Peripheral circuit of microcomputer (AX-6M00)
This circuit detects DC current flowing to power module: When over-current
(instantaneous value) flows, it stops upper and lower arm drive circuit and also
produces Ip signal to stop microcomputer.
This circuit detects DC current flowing to power module and produces signal to notify
microcomputer of overload status.
This circuit voltage-amplifies DC current level detected by detection resistor and sends
it to microcomputer. In addition, setting of internal/external overload judgment is
performed.
This circuit produces reset voltage.
12V
5V
0V
12V
5V
＋
IC4
− 8
5
＋
7
−
6
4
terminal
0V
0V
5V
0V
Basic operation
– 104 –
Outdoor
Microcomputer
（AX-6M00）
48 Reset
0V
9 IP cutter
SPM
60
Id
61 Is