11

ICs for TV

AN5637

s Application Circuit Example

Note) The following signal is inputted to Pin1 from the AN5192/95.

• System discrimination

1. Pin1 is the input and output pin for the three pieces of information

(1) Reference frequency signal input pin (AC)

(2) System discrimination signal input pin (DC voltage)

(3) SECAM/Non-SECAM discrimination output pin (DC current)

2. Reference frequency signal

The reference frequency signal input for Pin1 is used for the following 4 signals ;

(1) Bell filter automatic adjustement

(2) PLL(VCO) automatic adjustement

(3) Deemphasis automatic adjustement

(4) Ident discrimination

Be sure to input the high precision PAL carrier signal (4.43362 MHz) only in the vertical retrace period.

AN5637

Pin1 input

Pin1 sink current

Pin9, 10 output

System discrimination

DC voltage

SECAM

"H" (4.6 V)

175

µA

Color difference signal output

"L" (1.3 V)

175

µA

Open

Non-SECAM

"H" (4.6 V)

0

µA

DC voltage output

"L" (1.5 V)

0

µA

Open