28LF-94H - Sharp TV Service Manual (repair manual). Page 11

 
Supply Voltages Available/Not-Available In Stand-by, IC Requirement, Supply Location 
 
Supply 

depends on 
CRT 

NO 

large signal board FBT 

depends on 
CRT 

14V-A NO 

large 

signal 

board IC401,IC402(Audio 

amplifier) 

(-)14V-A NO 

large 

signal 

board IC401,IC402(Audio 

amplifier) 

14V 

NO 

large signal board Horizontal drive transistor 

8V 

NO 

small signal board

IC400 (MPIF)/Headphone discrete 

circuit/RGB pre amplifiers/audio saw 

filter(Z401) 

5V 

NO 

small signal board

IC400 (MPIF),Tuner(TU200,TU850) 

V8stby 

YES 

large signal board Step down IC and for s+5V 

1.8V 

YES 

small signal board IC313 (ADOC) 

3.3V 

YES 

small signal board

IC313 

(ADOC),IC309(EEPROM),IC316(Reset IC) 

12V 

NO 

small signal board CRT board (IC900) 

5V 

YES 

small signal board LED/IR 

Vert Sup+ (14V)  NO 

large signal board Vertical IC (IC100) 

Vert Sup- (-
14V) 

NO 

large signal board Vertical IC (IC100) 

33V 

NO 

large signal board Tuner (TU200,TU850) 

M24C64WBN6

 is the 64Kbit electrically erasable programmable memory. The memory is compatible with the I

2

C

standard, two wire serial interface, which uses a bi-directional data bus and serial clock.

This stage is designed with discrete components (no IC is used for this purpose)

Two groups of saw filters are used from EPCOS

For picture (Z400)
•

PAL SECAM BG DK L L’ÆK3953M

•

PAL SECAM BG  I I’ ÆK3953M

For sound (Z401)
•

PAL SECAM BG DK L L’ÆK9656M

•

PAL SECAM BG I I’ ÆK9356

For sound saw filter it needs to be switched between L’ and other standards for K3953M, a port signal coming from
PNX300X (ADOC) called SEL_L/L’ is used for this purpose to make pin2 of audio saw filter ground or not.