Drive Circuit For Reverse Solenoid; Reset Circuit - Toshiba MR-3011 Service Manual

10.8 Drive Circuit for Reverse Solenoid

TP49
RKNSOL_PWM
This circuit controls the closing/opening of the flapper of the reverse solenoid.
When the level of RKNSOL_PWM is "H", Q13 is turned ON and the flapper is closed. The drive signal for the
solenoid is a PWM signal. The flapper is closed in the maximum torque of the solenoid and the duty value
becomes 100% when the flapper is started to be closed. The duty value is then decreased down to 50% and the
flapper is kept closed while the temperature rising of the solenoid is lowered.

10.9 Reset Circuit

+5V
+ 1
C115
2
This circuit generates a CPU reset signal when the power is turned ON and the power voltage is cut off or
lowered instantaneously. This circuit has a watchdog timer for diagnosis of the CPU system operation.
The level of IC13-8pin (*RES) is normally "H" after the power is turned ON. However, when the power is turned
OFF or the voltage of the +5V power supply is decreased to 4.2V or lower for some reason, the level of IC3-8pin
becomes "L" and the CPU is reset. A clock with a fixed cycle is input to IC13-3pin (CK) from the CPU to clear the
watchdog timer of IC13. If the clock is not input from CPU due to a system error, the level of IC13-8pin becomes
"L" to reset CPU and system operation is stopped.
October 2000 © TOSHIBA TEC
R115
1 1 2
1
R116
2
SGND
2
RES
5
VCC
1
C57 *RES
IC13
2
4
GND
VREF
VS
7
1
C113
2
SGND
D12
2 1
D 2
Q13
3
G
S 1
PGND
A 2
D3
K 1
3
CK
8
1
CT
6
SGND
+
1
C116
2
10-7 MR-3011/3012 DESCRIPTION OF CIRCUITS
DF+24V
4
DF+24V CN5.4
5
*RSOL CN5.5
R125
1 2
WDT_CK
*RESET
1
C114
2
Reverse solenoid
RSOL