BA7181FS Datasheet, PDF (1/8 Pages) Rohm – 2-channel PRE / REC amplifier with auto-tracking interface

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.
•^Applications
VCRs
•^Features
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
AGC output). The AGC output level is 300mVP-P(Typ.);
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.
•^{Absolute maximum ratings (Ta = 25°C)}
Parameter
Symbol
Limits
Unit
Applied voltage
Power dissipation
VCC
7.0
V
Pd
937.5^∗
mW
Operating temperature
Topr
– 20 ~ + 65
°C
Storage temperature
Tstg
– 55 ~ + 150
°C
∗ When mounted on a 90mm × 50mm, t = 1.6mm glass epoxy board.
Reduced by 7.5mW for each increase in Ta of 1°C over 25°C.
•^{Recommended operating (Ta = 25°C)}
Parameter
Symbol
Playback / recording (voltage range)
VCC
á­ºNot designed for radiation resistance.
Min.
4.5
Typ.
5.0
Max.
5.5
Unit Conditions
V
11pin
1