BA3311L

Audio ICs Dual preamplifier with ALC BA3311L The BA3311L is a dual preamplifier with ALC designed for use in stereo radio-cassette recorders. It comes in a compact 12-pin ZIP package and has two record / playback preamplifiers, and an ALC circuit. The preamplifiers are directly coupled to the head and do not require coupling capacitors. This prevents tape head magnetization and ”pop” noise generation. An ALC circuit with large dynamic range can be constructed with addition of just an external detector and time constant circuit. FApplications Stereo radio cassette players FFeatures 1) The input block uses a bias circuit that does not require coupling capacitors. 2) ALC circuit requires addition of just an external detector and time constant circuit. FBlock diagram 3) Wide operating power supply voltage range. 4) High gain. 5) Low noise. 189 Audio ICs FAbsolute maximum ratings (Ta = 25_C) BA3311L FRecommended operating conditions (Ta = 25_C) FElectrical characteristics (unless otherwise noted, Ta = 25_C, VCC = 8V, and f = 1kHz) 190 Audio ICs FMeasurement circuit BA3311L FOperation notes (the value of the resistor marked with an asterisk in Fig. 2) Changing the input resistor Rg, and the ALC time constant influences the ALC transient characteristics. In particular, if Rg is less than 3.9kΩ or the time constant capacitor is less than 47µF, the ALC may operate excessively. Do not use smaller values than those recommended for these components. 191 Audio ICs FApplicatio...