BA3528AFP

Audio ICs Pre / power amplifier and motor governor for 3V headphone stereos BA3528AFP / BA3529AFP The BA3528AFP and AB3529AFP have been developed for headphone stereos. They run off a 3V power supply, and include dual pre- and power amplifiers, and a motor governor. The preamplifiers are direct-coupled, and the power amplifiers use a fixed-gain NF circuit. An on-chip VREF amplifier makes output coupling capacitors unnecessary, and the motor governor uses a bridge ratio system to minimize the external parts count and make reliable and compact designs possible. FApplications 3V portable stereo equipment FFeatures 1) All the functions required for headphone stereo units on a single chip. 2) Preamplifier includes a mute amplifier. 3) Direct-coupled preamplifier. 4) No output coupling capacitors required for the power amplifiers. 5) Power amplifiers do not require oscillation prevention measures. 6) Power amplifier gain allows use of noise reduction (BA3529AFP). FAbsolute maximum ratings (Ta = 25_C) FRecommended operating conditions (Ta = 25_C) 385 Audio ICs FBlock diagram BA3528AFP / BA3529AFP 386 Audio ICs BA3528AFP / BA3529AFP FElectrical characteristics (unless otherwise noted, Ta = 25_C, VCC = 3V, and f = 1kHz) BA3528AFP 387 Audio ICs BA3529AFP BA3528AFP / BA3529AFP 388 Audio ICs FMeasurement circuit BA3528AFP / BA3529AFP 389 Audio ICs FCircuit operation (1) Preamplifier In the preamplifier input stage the pin 22 bias is the input and the negative feedback ...