— 6 —
RESET CIRCUIT
When batteries are set or an AC adapter is connected, the reset IC provides a low pulse to the CPU. The
CPU then initializes its internal circuit, and clears the working storage RAM.
When the power switch is pressed, the CPU receives a low pulse of POWER signal. The CPU sends APO
signal to the power supply circuit, also sends a reset signal to the DSP.
LCD BACKLIGHT
When voltage CVDD is supplied, transistors Q501 and 502 start oscillation.
From the oscillation voltage, transformer T501 generates about 600 V which is necessary for lighting the
backlight.
Reset IC
IC2
RN5VD40AA
DSP
LSI2
HG51B277FB-1
VDD
Reset signal
To power supply circuit
VDD
Battery set
RESET
VDD
POWER
From power switch
NMI
APO
PLE
CPU
LSI1
GT-913F
SCKO
10
1
1
1
C502
(Bottom View)
NT-07
T501
CFL1
L501
LHL08TB101K
1
1
12
DG
CVDD
C104FA
C104M
2SD965R
2SD965R
C501
R501
4.7K
Q501
CP14
Q502
C516
1
12
23
32
2
HMBV26BG1W63N/AZ
DE0405-979SL180J2K
2
1
2
2
3
4
5
8
9
7
5
Summary of Contents for WK-1200
Page 16: ...15 SCHEMATIC DIAGRAMS Main PCB JCM730 MA1M 8 7 2 3 1 4 6 5...
Page 17: ...16 Sub PCB JCM730 MA2M 10 9...
Page 18: ...17 Console PCBs JCM730 CN1M CN2M CN3M CN4M...
Page 19: ...18 LCD Driver PCB JCM730 LCD1M...
Page 20: ...19 Keyboard PCBs JCM731T KY1M KY2M KY3M...
Page 25: ...8 11 10 Nishi Shinjuku Shinjuku ku Tokyo 160 Japan Telephone 03 3347 4926 MA0700571A...
