CIRCUIT DESCRIPTION

The main functions of the I.C. are following :

Video Switching

2 electronically switched inputs :

plug.

2 outputs :

Ω) for peri-TV

plug.

the TV set.

Each input and output is protected from ground

short-circuit. The 75

Ω output is protected through

a75

Ω resistor.

Audio Switching

Two electronically switched inputs :

- 300mV rms input coming from internal audio.

- 100mV rms input coming from the peri-TV plug

Inputs and outputs are also protected against

ground short-circuit.

Switching Logic

The logic takes into account the informations on 3

pins.

- Internal or external video and sound (pin 8 peri

TV plug)

- Band III information

- Video recorder key.

External Video and Audio signals are selected in

two cases.

- When there is a voltage information coming from

peri-TV plug.

- When the video recorder key is selected (on TV

front panel) and programmed on band III.

This I.C. includes an internal switch (open collector

transistor) which commutes the time constant of

the horizontal PLL circuit in case of video recorder

reception.

APPLICATION CIRCUIT

TEA1014

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