Sony KZ-32TS1U Training Manual page 57

Power ON sequence
After the Main Micro IC9004 (M board) receives standby power (CN1921/pin 16), IC9004 can respond to the
power ON command from either the remote (IR) or the switch on the front panel H3 board. The TV power ON
steps are:
1. The front panel power ON button is pressed. CN1921/pin 48 goes LOW (0Vdc – see Figure 25-2 for the
location of CN1921/CN9001).
2. Main Micro IC9004 outputs a HIGH (5Vdc) to energize the power relay. CN1921/pin 21 goes to 5Vdc.
3. This 5Vdc passes through the A board into the power supply (G) board at CN1605/pin 5 = 5Vdc.
4. If the Bi-metal fuse under the lamp fan 2 is closed (CN1614/pin 1 & 3 connected), then the power ON
command into CN1605/pin 5 = 5Vdc can energize the power relay RY1601 on the A board.
5. Within the G board, power relay RY1601 contacts close, passing AC to the Main power supply. The Main
power supply outputs various voltages to power the TV.
6. Only the +15 voltages (CN1606/pin 2, 6) that go to the audio output stage are fused. Fusible resistors are in
the 33Vdc and 17Vdc outputs at CN1605/pin 1, 2.
Rear Panel
CN9001
1
M
Connectors
FIGURE 25-2 - TV BOARD ASSEMBLY
BOTTOM VIEW OF A BOARD
VHF
BB BC
Board
55
25. Power Supply
Bottom
A Board