Casio PK-5 User manual

ELECTRIONIC KEYBOARD
PK-5
(without price)

CONTENTS
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Circuit Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
PCB View and Major Waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Schematic Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
IC Lead Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Exploded Veiw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

— 1 —
SPECIFICATIONS
General
Number of Keys: 32
Polyphonic: 2-note
Preset Tones: 16
Auto-Rhythms: 19; Rock 1~2, 16 Beat 1~2, Disco 1~3, Pops 1~3, Slow Rock, Swing
March, Reggae, Tango, Samba, Bossa Nova, Beguine, Waltz
Accompaniment Patterns: 13; Rock, Pops, Funk, Slow Rock, Latin, Jungle, Orient, Bagpiper,
Fanfare, Child's Play, Classical, Computer, New Age
Demonstration Tune: Classical Medley
Built-In Speaker: 6.5 cm dia. 0.5 W Input Rating: 1 pec.
Power Source: 4 AA size dry batteries
Battery life: Approx. 3 hours (SUM-3/R6P)
Approx. 6 hours (AM-3/LR6)
Power Consumption: 0.7 W
Dimentions: 41 x 375 x 115 mm (HWD)
(1-5/8 x 14-3/4 x 4-1/2 inches) (HWD)
Weight: 0.4 kg (0.9 lbs) excluding batteries
Electrical
Current Drain with 6V DC:
No Sound Output 35 mA ±20%
Maximum Volume 113 mA ±20%
with keys C4 and E4 pressed in Flute tone
Volume: Maximum, Accmpaniment: Latin,
Tempo: Maximum
Minimum Operating Voltage: 5.0 V

BLOCK DIAGRAM
Nomenclature of Keys
F#3 G#3 A#3 C#4 D#4 F#4 G#4 A#4 C#5 D#5 F#5 G#5 A#5
F3 G3 A3 B3 C4 D4 E4 F4 G4 A4 B4 C5 D5 E5 F5 G5 A5 B5 C6
KO0~KO6
KI0~KI7
Keyboard
Switches
Oscillator
X1
Amplifier
AN8053N
IC1
Speaker
CPU
MSM6387-03
LSI1
— 2 —

CIRCUIT DESCRIPTION
Key Matrix
CPU (LSI1: MSM6387-03)
Containing a sound data ROM and a DAC (Digital to Analog Convertor), the CPU provides sound wave-
form in accordance with the pressed key and the selected tone.
The following table shows the pin functions of LSI1.
— 3 —
KI0 KI1 KI2 KI3 KI4 KI5 KI6 KI7
KO0 F3 F#3 G3 G#3 A3 A#3 B3 C4
KO1 C#4 D4 D#4 E4 F4 F#4 G4 G#4
KO2 A4 A#4 B4 C5 C#5 D5 D#5 E5
KO3 F5 F#5 G5 G#5 A5 A#5 B5 C6
KO4 Tone 0 Tone 1 Tone 2 Tone 3 Tone 4 Select
KO5 Tone 5 Tone 6 Tone 7 Tone 8 Tone 9 Stop
KO6 Demo
Tempo
Up
Tempo
Down
Volume
Up Volume
Down
Pin No. Terminal In/ Out Function
1, 2 TEST1, TEST2 Not used. Connected to ground.
3 RESET In Power ON reset input. On: +6 V Off: 0 V
4 AVDD In +5 V sorce for the built-in DAC
5 OUT Out Sound waveform output
6 AGND In Ground (0 V) source for the built-in DAC
7 GND In Ground (0 V) source
8, 9 COSI, COSO In/Out 21.725 MHz clock pulse input/output
10 VDD In +5 V source
11 ~ 18 KI0 ~ KI7 In Input terminal from keys and switches
19 ~ 23 KO11 ~ KO7 Not used.
24 ~ 30 KO6 ~ KO0 Out Key and switch scan signal output

Amplifier/Voltage Regulator (IC1: AN8053N)
Consisting of an amplifier and a voltage regulator, AN8053N amplifies the sound signal from the CPU and
also provides the CPU +5V source.
The following figure shows the internal block diagram of IC1.
TROUBLESHOOTING
16 15 14 13 12 11 10 9
8
7
6
5
4
32
1
SP AMP VREF
5V REG
POWER
SPO NC SP GND PC-1 PC-2 SPI SPM VREF
VCC NC CONT 5V
VREG NCNC NC PRE GND
+
-
— 4 —
Checkpoint
Pin 13 should have +5 V.
An amplified waveform should be observed at pin
1.
Voltage at pin 3 of the CPU should be raised from
0V to +5 V when the power switch is turned on.
Switch contact.
Pins 24 ~ 30 should provide pulses.
Pin 5 should provide a sound waveform when a
key is pressed.
Pins 8 and 9 of the CPU should receive an oscil-
lation signal.
Nature of Trouble
No sound at all
Certain key(s) or
switch(es) do(es) not
work.
Faulty Block
Power amp.
(IC: AN8053N)
Power Switch
CPU
(LSI1: MSM6387-03)
Oscillator (X1)
Key or Switch Contact
Open Circuit on KO or KI
Lines

PCB VIEW and MAJOR WAVEFORMS
M3205-MA1M PCB
— 5 —
2
1
3
45
Clock pulse COSO
MSM6387-03 Pin 9 Key scan signal KO0 MSM6387-03 Pin 30
Key scan signal KO1
MSM6387-03 Pin 29
Sound output
MSM6387-03 Pin 5
Tone : Piano
Key : G4
Power Amp. output
AN8053N Pin 1
Tone : Piano
Key : G4
Volume : Max.

— 6 —
SCHEMATIC DIAGRAM
1
23
4
5
6.0
0.5 0.5 0.5 0.5 0.5 0.5 0.5
5.2 4.8 2.5
2.2 2.2 4.9
0.0
0.0 0.0
0.0 5.2 0.0
0.0 3.9 3.1 4.0 4.0
M3210-MA1M PCB

LSI1: MSM6387-03
30 29 28 24 27 26 25 23 22 21 20 19 18 17 16
TEST2
TEST1 RESET GND AVDD OUT AGND COSI COSO VDD KI0 KI1 KI2 KI3 KI4
1 2 3 7 4 5 6 8 9
10 11 12 13 14 15
KO0 KO1 KO2 KO6 KO3 KO4 KO5 KO7 KO8 KO9
KO10 KO11
KI7 KI6 KI5
1 2 3 4 5 6 7 8
16 15 14 13 12 11 10 9
SPO NC SPG PC-1 PC-2 SPI SPM VREF
VCC
NC
CONT
VREG
NC NC NC
PR GND
IC1: AN8053N
IC LEAD IDENTIFICATION
— 7 —

EXPLODED VIEW
— 8 —
7
A
3
8
9
04
5
6
1
C
2
B
D