BA7746S Datasheet, PDF (9/12 Pages) Rohm – VCR Hi-Fi audio signal REC / PB amplifier

Video ICs
•^{Control mode tables}
(1) REC / PB control
Switch between REC and PB using pin 12.
Control pin
REC / PB
H
Mode
REC
REC AMP
ON
L
PB
OFF
BA7746S / BA7746FS
Function
PRE AMP
REC + B SW
OFF
ON
ON
OFF
HEAD SW (P)
OFF
ON
(2) OVER REC control
Control for OVER REC (current emphasis) is done using pin 9.
When in OVER REC mode, the gain setting is recording
amplifier AGC level + 1.9dB.
Control pin
OVER REC
H
L
Mode
Function
REC AGC Level
OVER REC
60.0mAP-P
—
48.2mAP-P
(3) REC MUTE control
Control for REC MUTE when recording is done using pin 8.
Control pin
REC MUTE
H
L
Mode
REC MUTE
—
Function
REC AMP
OFF
ON
(4) EP / SP control
EP / SP control during playback is done using pin 4. When
EP is selected, the gain of the playback amplifier is increased
by 5dB over its normal setting.
Control pin
EP / SP
H
L
Mode
EP
SP
Function
PRE AMP gain
Typ. + 5dB
Typ.
9