818
Audio ICs
Low power consumption headphone
driver for digital audio
BA3577FS
The BA3577FS is a headphone driver developed for portable digital audio equipment that supports a voltage of 1.5V.
Applications
Portable MD players and others
Features
1) 1.5V supported.
2) Low current consumption
(At PO = 0.5mW / ch, VCC inflow current = 3.3mA, and
B inflow current = 6.8mA (Typ.)).
3) Output coupling capacitor of 100µF produces fC =
45Hz (RL = 16Ω).
4) Internal muting switch.
5) Internal ripple filter.
6) Internal BEEP circuit.
Absolute maximum ratings (Ta = 25C)
Recommended operating conditions (Ta = 25C)
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Audio ICs BA3577FS
Block diagram
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Audio ICs BA3577FS
Pin descriptions
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Audio ICs BA3577FS
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Audio ICs BA3577FS
Electrical characteristics (unless otherwise noted, Ta = 25C, VCC = 2.8V, B = 1.2V, PWSTB = 2.8V, MUTE = 0V,
RL = 16Ω, f = 1kHz, DIN AUDIO)
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Audio ICs BA3577FS
Measurement circuit
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Audio ICs BA3577FS
Measurement conditions
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Audio ICs BA3577FS
Circuit operation
(1) The BA3577FS operates at the timing chart shown below, which prevents popping noises in the headphone output.
(2) The ripple filters (pins 1 and 2) and bias amplifiers (pins 3 and 4) of the BA3577FS cannot be used as external power
supplies or reference voltages.
(3) The BA3577FS outputs a BEEP signal only when the PWSTB pin (pin 7) and the MUTE pin (pin 9) are HIGH. Also,
input a rectangular waveform of 500Hz to 5kHz with an amplitude from the GND to VCC to the BEEP IN pin (pin 11).
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Audio ICs BA3577FS
Application example
Electrical characteristic curves
External dimensions (Units: mm)
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Audio ICs BA3577FS
