Tv Start-Up, Tv Normal Run And Stand By Mode Operations; Tv Start-Up Operations; Tv Normal Run And Stand-By Mode Operations - Daewoo DDT-21H9ZDF(21") Service Manual

Service Manual CP-099/FS

5-10 TV start-up, TV normal run and stand by mode operations

5-10-1 TV start-up operations

* Schematic diagram for start-up operations
STAND BY
SW801 CONTROLLER
POWERSW
CP-099
D801~D804
(BRIDGE)
D806~D809
(BRIDGE)
SMPS IC
* TV start-up and microcontroller initialization.
- When AC POWER is on, rectified voltage is applied to transformer. T802. That voltage is rectified by
D801, D802, D803, and D804. T802. transformer is controlled by I802 and makes DC 5V at pin 11.
- When POWER SWITCH(SW01) is pushed on, voltage (5V / 3.3V) are supplied at I501 (pin3, 15 /
25,54).
- Reset voltage is applied at RESET pin(58) of I501.
- Microcontroller(I501) starts a initial operation, POWER(pin5) is high. Then the secondary voltages of
the T801 are applied.
- The microcontroller consults I502 EEPROM via IIC bus to know the last TV set mode (normal run
mode or stand-by mode) before switchins off.
Photo
I802
4 4
coupler
5
5
T802
STAND BY
2
TRANS FORMER
I801
3
SMPS
4 TRANS FORMER
3
I801
1
SW01
POWER SW(CP-099FS)
11
I504
Reset
10
I808
5 V
-55-
Q516
Q517
I503
3.3 V
L501 L502
3 15 54
5 V 5 V 3.3 V
5 POWER
I501
VCT 383X
58
Reset
SCL SDA
59 60
6 5
I502
8
EEP ROM
25
3.3 V
5 V
45