The TLV320AIC22C has a flexible serial interface that allows the two channels of the TLV320AIC22C to be interfaced to a single multichannel buffered serial port (McBSP) of the external digital signal processor (DSP). The two channels share the digital interface at different time slots. Up to four TLV320AIC22C units can be cascaded together to obtain eight channels. For control purposes, either the serial interface or the inter-integrated circuit (I2C) interface can be used. Programmable-gain amplifiers (PGAs), preamp gain, microphone bias voltages, and analog crosspoint are programmed through the serial interface or the I2C interface. The TLV320AIC22C can be powered down, via a dedicated terminal or by using software control, to reduce power dissipation.