— 6 —
FILTER BLOCK
Since the sound signals from the CPU is stepped waveforms, the filter block is added to smooth the waveforms.
POWER AMPLIFIER (IC101: TA8248K)
The power amplifier is a two-channel amplifier with standby switch.
The following table shows the pin function of IC101.
Pin No.
Terminal
In/Out
Function
1
NC
—
Not used
2
B.S.2
—
Terminal for a bootstrap capacitor
3
OUT2
Out
Channel 2 output
4
VCC
In
+9 V source
5
OUT1
Out
Channel 1 output
6
B.S.1
—
Terminal for a bootstrap capacitor
7
Power GND
In
Ground (0 V) source
8
Stand by
In
Power control signal input. 0 V: Off, +9 V: On
9
DC
—
Terminal for a decoupling capacitor
10
NF1
In
Negative feedback input
11
IN1
In
Channel 1 input
12
IN2
In
Channel 2 input
13
NF2
In
Negative feedback input
14, 15
Pre GND
In
Ground (0 V) source
Amp.
TA8248K
Filter
Block
CPU
MSM6755B-17
Summary of Contents for CTK-401
Page 11: ...9 PRINTED CIRCUIT BOARDS Main PCB JCM442 MA1M Top View Bottom View 1 2 3 4 5 8 9 6 7...
Page 12: ...11 SCHEMATIC DIAGRAMS Main PCB JCM442 MA1M 6 7 1 9 8 5 4 3 2...
Page 13: ...12 Sub PCB JCM442 MA2M...
Page 14: ...13 Keyboard PCBs KDM4910K KY1M KY2M...
Page 16: ...15 EXPLODED VIEW 18 14 13 15 12 11 19 17 16 10 R 1 R 2 R 3 5 6 8 7 9 4 R 4 R 6 R 5 4 3 1 2...
Page 19: ...MA0600571A...
