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7-1
CIRCUIT DESCRIPTION
TABLE OF CONTENTS
Page
1. Audio circuit ----------------------------------------------------------------------------------------- 7-2
1.1 Audio input ------------------------------------------------------------------------------------ 7-2
1.2 Audio output ----------------------------------------------------------------------------------- 7-2
2.
Power
supply ------------------------------------------------------------------------------------- 7-2
3. On-screen circuit --------------------------------------------------------------------------------- 7-3
4. Video input circuit -------------------------------------------------------------------------------- 7-3
5. Definition converter LSI peripheral circuit ------------------------------------------------- 7-3
6. System reset, LED control circuit ------------------------------------------------------------ 7-4
6.1 System reset ------------------------------------------------------------------------------------ 7-4
6.2 LED control circuit ----------------------------------------------------------------------------- 7-4
7.
E
2
PROM for PnP -------------------------------------------------------------------------------- 7-4
8.
E
2
PROM ----------------------------------------------------------------------------------------- 7-4
9. CPU circuit ---------------------------------------------------------------------------------------- 7-4
9.1 Detection of POWER switch status -------------------------------------------------------- 7-4
9.2 Display mode identification ------------------------------------------------------------------ 7-4
9.3 User Control ------------------------------------------------------------------------------------- 7-6
9.4 Control of definition converter MCU I306 ------------------------------------------------ 7-6
9.5
I
2
C bus control ---------------------------------------------------------------------------------- 7-7
9.6 Power ON sequence -------------------------------------------------------------------------- 7-7
9.7 Power OFF sequence ------------------------------------------------------------------------ 7-8
10.
Inverter ------------------------------------------------------------------------------------------- 7-9
10.1 Circuit Diagram ------------------------------------------------------------------------------- 7-9
10.2
Inverter
basic
function ----------------------------------------------------------------------- 7-9