Specifications

CA10 Course Notes

Sharp Electronics (UK) Limited

CE Technical Support Group Page 1

Introduction to the CA10 Chassis

As with the last Sharp colour television chassis ( CS ) the new CA10 design incorporates the latest

technology from Japan and Spain where the receivers are designed and manufactured at the production

plant in Barcelona.

Once again the reliable switched mode power supply, based around a field effect transistor, is used to

provide power for the operation of the set. This has changed little since the CS chassis, but a detailed

explanation of its circuit operation is given in the following pages.

Extensive use is made of dedicated integrated circuits and the number of surface mounted IC’s is kept

to a minimum to maintain an easier level of serviceability. The majority of IC packages are of the dual

in line type. A break down of the major IC’s explaining their basic functions is outlined below.

IC101 is the only large surface mounted IC and provides overall system control.

IC104 stores all the user information such as tuning and picture settings as well as geometry

and CRT drive characteristics. This is an eight pin surface mounted device

IC105 is the EPROM, which contains the program to run the main system microprocessor.

IC106 ( STV5346 ) is a single chip teletext decoder/processor whose output is at RGB levels.

This

is a 28 pin surface mounted device.

IC201 ( TDA8844 ) provides the time base generators ( line and frame ), IF stage, majority of the

Y/C processing and video switching ( including RGB ).

IC304 ( M5218L ) is the headphone amplifier.

IC305 ( MSP3410D ) provides all the audio signal processing requirements, including decoding,

volume control and signal switching.

IC401 ( HEF4053 ) provides for video switching ( including the Y and C signals ).

IC702 provides primary power supply on/off control and communication with the main system

processor for key scan and remote control functions. It also controls the receivers self timer

operation.

IC901 ( TDA6107Q ) drives the CRT.

Note that IC101 and IC702 are produced by Sharp and therefore can only be obtained through the Sharp

Spare Parts Centre. IC104 and IC105 are generally available, but contain programs and therefore must

also be obtained direct from Sharp Spare Parts Centre.

As the tuner is directly controlled by the I C bus it enables direct channel entry and stable control of the

tuning and AFT functions. By receiving controlling inputs from IC201 ( IF processor ) and IC106 ( teletext

processor ) the main system processor can carry out automatic tuning and sorting.

Various audio inputs can be used to generate either mono, stereo or SRS ( Sound Retrieval System )

sound, depending on receiver specification - see next page for model specifications. Output from the top

of the range receiver is 2 x 20W ( MPO ) and an additional 20W from the external sub-woofer. As the

audio signal is controlled by the data bus, it is possible to have separate control of both loudspeaker and

headphone outputs.

Video switching from a number of sources is possible, this includes RGB from a rear SCART socket and

S-VHS from the rear AV SCART socket.

All of the above contribute to make a reliable and easily repairable television chassis, that is fitted into

all of the new Sharp range of large screen television receivers as listed on the following page.