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Video ICs

2-channel PRE / REC amplifier with

auto-tracking interface

BA7181FS

The BA7181FS is a PRE / REC amplifier developed for use in video cassette recorders. It has been designed for use

in two-head decks and features built-in FB damping, two preamplifiers, a chroma output amplifier, an FM output

amplifier (with AGC), an envelope detector, a constant-current BTL-drive REC amplifier (with AGC)and built-in chan-

nel and REC / PB switches on a single monolithic IC.

VCRs

1) The playback amplifier has a total gain of 57dB

(Typ.), and has a low-noise preamplifier. Designed

for VHS-band operation with low external parts

count. The IC has two circuits for two-head VCR

applications.

2) Two playback output systems (through output and

suitable for FM brightness signal output.

3) Auto-tracking interface is provided for automated

tracking adjustment. The detector characteristic is

linear, and the sensitivity can be adjusted using

external components.

4) The recording amplifier uses constant-current BLT

drive that handles load variations (i.e. head imped-

ance)well, and gives stable recording characteris-

tics. A single circuit is provided for two-head VCR

use.

5) Built-in recording level AGC means adjustment of

FM recording current is not necessary.

6) Head switches for two-channel PRE / REC system

provided.

7) Operates off a single 5V power supply, with low

power dissipation.

Parameter

Symbol

Limits

Unit

Applied voltage

Power dissipation

Operating temperature

Storage temperature

7.0

V

Pd

mW

Topr

°C

Tstg

°C

Reduced by 7.5mW for each increase in Ta of 1

°C over 25°C.

– 20 ~ + 65

– 55 ~ + 150

Parameter

Symbol

Min.

Typ.

Max.

Unit

Conditions

Playback / recording (voltage range)

4.5

5.0

5.5

V

11pin

Not designed for radiation resistance.