Файл:BA3406AF.pdf

Audio ICs

Dual preamplifier with mute function BA3406AF The BA3406AF is a multi-function dual-channel preamplifier with a built-in mute circuit and a time-constant switching circuit for use with metal tape. The output circuits have diodes, and can be connected to other circuits in parallel, which eliminates the need for switches. The mute circuit is independent of the preamplifier block, and can be used to mute the whole system. FApplications Car stereos, radio cassette players, and tape decks FFeatures 1) Wide operating power supply voltage range (6V to 14V). 2) Low noise (VNIN = 1.0µVrms Typ.). 3) High open loop voltage gain (GVO = 80dB Typ. at pins 1 and 15). 4) Two channels on one chip, providing good channel balance. 5) Emitter-follower outputs for low output impedance. 6) Built-in switching circuit for use with metal tape. 7) Built-in mute circuit.

FBlock diagram

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8) Mute and metal-tape circuits are independent from the preamplifier circuit to allow greater design freedom. 9) The output circuits have diodes to prevent current backflow and enable parallel connection to other circuits. 10) The resistor for the CR circuit that sets the metaltape circuit time constant to 70µs is on the chip. Setting the time constant only requires addition of an external capacitor.