The LP3950 is a color LED driver with built in audio synchronization feature for any analog audio input such as polyphonic ring tones and MP3 music. The LEDs can be synchronized to an audio signal with two methods: Amplitude and Frequency. Also several fine tuning options are available for users for differentiation purposes. The chip also has an unique AGC (Automatic Gain Control) feature which tracks the input signal level and automatically adjusts the gain to optimal value.