The Si3000 is a complete solution for voice I/O such as handsets in multi-function printers. It can be connected directly to any high-speed, ISOmodem system-side chip to support a telephone handset. An extended AT command set is available to control the Si3000.
In addition to a codec (A/D, D/A), the device integrates a microphone preamplifier, three-input mixer, +12.5 to –34.5 dB of programmable gain, headphone/speaker driver, and an integrated handset hybrid for direct connection to a two-wire telephone handset. Programmable gain and attenuation settings are available on both the A/D converter and the D/A converter signal paths with 1.5 dB step resolution. Programmable gain/attenuation is implemented using a zero crossing technique to enable “click-free” level transitions. Operation from a single +5 V or a single +3.3 V power supply makes the device suitable for low power portable applications.