No. 5765-8/14

LA7567N, 7567NM

Pin Descriptions

Pin No.

Pin

Description

Equivalent circuit

1

SIF INPUT

• SIF input. The input impedance is about 1 k

Ω. Since

buzzing and buzz beating can occur if interference enters

this input pin, care must be taken when design the pattern

layout for this pin. Note that the video and chrominance

signals are especially likely to interfere with the audio

signal. Also, the VIF carrier signal can also cause

interference.

2

FM power supply filter

• FM detector bias line filter input. Used to improve the FM

detector signal-to-noise ratio.

C1 should be at least 0.47 µF, and 1 µF is recommended.

If the FM detector is not used, connect pin 2 to ground

through a 2-k

Ω resistor. This stops the FM detector VCO.

3

4

SIF converter

• Pin 3 is the SIF converter output. The signal is passed

through a 6-MHz bandpass filter and input to the SIF

circuit. There is a 200-

Ω resistor in series with the emitter-

follower output.

• Pin 4 is the SIF converter 500-kHz oscillator connection.

Since this oscillator circuit includes an ALC, the oscillator

level is held fixed at a low level. If this circuit is not used,

connect pin 4 to ground through a 10-k

Ω external resistor.

Providing this external resistor stops the 500-kHz oscillator

and allows the converter to be used as an amplifier.

5

and ground.

Continued on next page.