* Attenuator gain range: 52dB (between Transmit and Receive)
* For line-powered applications : 3~6.5V low voltage operation
* For improved sensitivity :4-point signal sensing
* For Transmit and Receive paths: background noise monitors
* External resistors set microphone amplifier gain
* Mute function included
* Chip disable: active or standby operation
* During dial tone presence: dial tone detector to inhibit receive idle mode