Skyworth 3T66/4T66 Chassis Service Manual

Service manual for Skyworth 3T66 and 4T66 chassis covering chip principles, power supply, and debugging.

Brand: Skyworth
Category: Television
Document type: Service Manual
Language: Chinese
Pages: 20
File format: PDF
File size: 411 KB
Updated: 24 October, 2026
MD5 checksum: F42CC25050E52E8DD22CBB672FC78677
PDF: Skyworth 3T66/4T66 Chassis Service Manual PDF

About this manual

This document is a service manual for the Skyworth 3T66 and 4T66 chassis, which utilize the Toshiba TMPA8873 super chip and the Beijing PLM PLM1000 high-definition signal format conversion chip. The manual details the principles, main functions, and chip introductions for these analog-digital high-definition color TV chassis. This manual is written in Chinese.

What's inside

3T66/4T66 Chassis Overview
Main Chip Introduction (TMPA8873)
PLM1000 Chip Introduction
System Block Diagram
Chip Pin Function Tables
Power Supply Sequence
Crystal Oscillator Settings
I2C Bus Control
Video Signal Processing
Debugging Parameters

Specifications

Main Chips	Toshiba TMPA8873, Beijing PLM PLM1000
Supported HD Formats	720P/50Hz, 720P/60Hz, 1080I/50Hz, 1080I/60Hz
Channel Memory	256 channels
MCU Core	TLCS-870/X series
OSD Characters	384 patterns, 12x32 grid

Frequently asked questions

What is the power-up sequence for the TMPA8873 chip?

First provide +5V to the MCU, then provide H-Vcc at least 100ms later, and finally provide other power supplies.

What is the function of the PLM1000 chip?

It converts high-definition signal formats (720P/50Hz, 720P/60Hz, 1080I/50Hz, 1080I/60Hz) into 576I or 480I.

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