Audio ICs Audio digital potentiometers BH3532FS The BH3532FS is a digital potentiometer designed for use in audio devices. Its built-in 22kΩ resistance systems can be used to set the data from the microcomputer in 256 steps. Applications Volume of recording and playing Features 1) Resistance can be set to any of 256 steps using digital codes (serial data). 2) Two built-in channels (Lch, Rch) 3) SSOP-A20 package Absolute maximum ratings (Ta = 25C) Recommended operating conditions (Ta = 25C) Block diagram 549 Audio ICs Pin descriptions Input / output circuits 550 BH3532FS Audio ICs BH3532FS Electrical characteristics (unless otherwise noted, Ta = 25C, VCC = 3.5V) Measurement circuit 551 Audio ICs Circuit operation The BH3532FS has two 22kΩ variable resistance systems which can be set in 256 steps (86Ω intervals). Resistance can be set in 256 steps using the MSB first 8-bit data. Input data is 17-bit serial data. The first bit is always “L”. The next eight bits set the resistance for wiper 1. The last eight bits set the resistance for wiper 0. 552 BH3532FS Input data is effective when the EN terminal is set to “H”, and is put on hold when the EN terminal is set to “L”. Also, the reading of the data is performed when CLK rises. When input data is effective, the previous output data is output serially to the DOUT terminal. See the figures below for more details. Audio ICs BH3532FS Electrical characteristic curves External dimensions (Units: mm) 553