ICD-MS1 (serv.man2) - Sony Audio Service Manual (repair manual). Page 19

Copying is strictly prohibited 

19

 

 
1.    MEMORY STICK – SYSTEM CONTROLLER IC722 
The system controller IC722 outputs the data read-out command from pin-12 [MS DIO] in synchronization with the clock output from pin-13 [MS CLK] and the bus state signal 
that is output from pin-11 [MS BS]. When the controller inside the Memory Stick receives the data read-out command, the data that correspond to the command are read from 
the FLASH RAM area of the Memory Stick. Then the controller inside the Memory Stick converts the read-out data to the serial data. The serial data are output to the system 
controller IC722 in synchronization with the clock input from the system controller IC722 and the bus state signal. The system controller IC722 converts the read-out data to the 
parallel data and the parallel data are output to the 2M-bit S-RAM IC727 sequentially via bus line. The 2M-bit S-RAM converts the data in reverse order of the recording. 
 
2.    SYSTEM CONTROLLER IC722 – ADPCM IC164 
The audio data that are read from the Memory Stick, are input to pin-24 [IR] of the ADPCM IC164 from pin-20 [DSPTX] of the system controller IC722 via signal processing 
circuit inside the system controller IC722 in synchronization with the bit clock of pin-77 [XBCK] and the sync signal output from pin-159 [SYNC] of the system controller IC722. 
The data are ADPCM-demodulated inside IC164 and are output from pin-23 [PCMRO] of IC164 in synchronization with the bit clock of pin-28 [SYNC] and the fall-down edge of 
the sync signal input to pin-28 [SYNC] of the ADPCM IC164. After this signal is input to pin-22 [PCMRI] of IC164, it passes through a low-pass filter and D/A converter inside 
IC164, and is converted to the analog signal that is output from pin-11 [VFRO] of IC164. 
 
During playback, the playback speed selector switch S763 controls the playback speed by changing the voltage at pin-172 [SPEED] of the system controller IC722 and thus by 
changing the output frequency (input to pin-28 [SYNC] of the ADPCM IC164) from pin-159 [SYNC] of the system controller IC722. (Refer to Table 3-1.) 
 

         Table 3-1 Playback speed and SYNC input frequency 

Mode Fast Normal 

Slow 

SP 

13.2 kHz ( +20% ) 

11.0 kHz 

9.4 kHz ( -15% ) 

LP 

10.4 kHz ( +30% ) 

8.0 kHz 

6.8 kHz ( -15% ) 

 

22

23

24

28

29

11

11

12

13

77

159

20

172

MEMORY

STICK

IC727

S.RAM

IC722

SYSTEM CONTROLLER

MS BS

MS DIO

MS CLK

BS

DIO

SCK

D0

D15

A1

A17

I/O1

I/O16

A0

A16

DSPTX

SYNC

XBCK

SPEED

BCLK

SYNC

IR

PCMRO

PCMRI

IC164

ADPCM

VFRO

D/A

PCM

EXPANSION

APPCM

DEMODULATION

S763

Playback speed

Fast

Normal

Slow

Analog 
audio 
output

 

Fig. 3-3 Playback circuit block diagram