
Audio ICs
Dual preamplifier with ALC detector
circuit
BA3314F
The BA3314F is a dual preamplifier IC with built-in ALC detector circuit, designed for audio applications. It comes in a
compact 14-pin SOP package, and has two record/playback preamplifiers, and an ALC detector circuit. The preamplifier
can be directly coupled to the tape head without coupling capacitors to prevent tape head magnetization and “pop” noise
generation.
With the built-in ALC detector circuit, an ALC circuit with large dynamic range can be constructed with addition of just
an external time constant circuit.
Applications
Audio equipment
Features
1) Input bias circuit does not require coupling capacitors.
2) Built-in ALC circuit with external time constant circuit.
Block diagram
3) Wide operating power supply voltage range.
4) High gain.
5) Low noise.
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Audio ICs BA3314F
FAbsolute maximum ratings (Ta = 25_C)
FRecommended operating conditions (Ta = 25_C)
FElectrical characteristics (unless otherwise noted, Ta = 25_C, V
CC = 8V and f= 1kHz)
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Audio ICs BA3314F
Measurement circuit
Operation notes
Changing the input resistor R
g, and the ALC time
constant influences the ALC transient characteristics. In
particular, if R
g is less than 3.9kΩ or the time constant ca-
pacitor is less than 47µF, the ALC may operate excessively. Do not use smaller values than those recommended for these components.
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Audio ICs BA3314F
Application example
Electrical characteristics curve
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External dimensions (Units: mm)