100-mΩ audio jack switch with autonomous microphone & ground detection

The TS3A225E is an audio headset switch device. The device detects the presence of an analog microphone and switches a system analog microphone pin between different connectors in an audio stereo jack. The microphone connection in a stereo connector can be swapped with the ground connection depending on manufacturer. When the TS3A225E detects a certain configuration, the device automatically connects the microphone line to the appropriate pin. The device also reports the presence of an analog microphone on an audio stereo jack.

In some systems, it is desirable to connect the stereo jack pin to ground. The TS3A225E provides two internal low resistance (<100mΩ) FET switches for ground shorting.