Casio WK-1500 Electronic Keyboard User Manual


 
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VDD
Battery set
RESET
CPU
LSI14
HD6433294A19F
Reset IC
IC13
RH5VL36AA
Working Storage RAM
LSI15
TC55257DFL-70L
DSP
LSI11
HG51B155FD-1
Key Controller
LSI16
HG52E35P
DVDD
DVDD
DVDD
VDD
VDD
-RESET
POWER
From power switch
KO Signal Generator
LSI17
UPD65611GB-019-3BA
-NMI
To power supply circuit
APO
P42
POWER AMPLIFIER (IC201: LA4620)
The power amplifier is a two-channel amplifier with standby switch.
6
16 2 10 11 13
12
Pre-drive
Amp.
Input
Amp.
Power
Amp.
+
–
Pre-drive
Amp.
Input
Amp.
Power
Amp.
+
–
9
7
3
5
+
–
Input
Amp.
Pre-drive
Amp.
Power
Amp.
+
–
Input
Amp.
Pre-drive
Amp.
Power
Amp.
4
19
20
21
22
23
1
18
17
15
14
8
RL Short
Protector
RL Short
Protector
Terminal
Protection
Circuit
Pop Noise
Prevention
Circuit
Ripple
Filter
IN11+
IN11–
IN12–
IN21+
IN21–
IN22–
NC DC MUTE ADJ
Boot11
OUT11
PoGND1
OUT12
Boot12
VCC1
Boot21
OUT21
PoGND2
OUT22
Boot22
VCC2
PriGND
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 provides APO
signal to the power supply circuit and raises RESET signal to +5 V to reset the DSP, the key controller and
the KO signal generator.
IC17
UPD65611GB-019-3BA
LG
CPU
LSI14
HD6433294A19F
LVDD
P40
P41
KO0 ~ KO3, KO5
IC301
BA612
LED Driver
Q15 ~ Q18
LED Driver
LD0 ~ LD7
La ~ Lg, Lp
KO Signal Generator
LED DRIVING