National Semiconductor: LM4970 – Audio Synchronized Color LED Driver
The LM4970 is a LED driver with an audio synchronization mode that virtually eliminates the need for real time software processing for LED lighting effects. The LM4970 includes three individual PWM color LED drivers that provide up to 42mA of current drive for each PWM LED output.
The LM4970 features an audio synchronization mode where the audio input signal that is mixed in from three audio inputs is filtered into three frequency bands, with each frequency band assigned to a specific PWM LED driver. The PWM LED drivers can also be directly programmed through an I2C compatible interface for applications where user defined LED pattern, color, and intensity programmability is a priority.
The LM4970 also features an audio input gain control which allows the user to increase the gain if the audio input signal does not create a bright enough effect on the LEDs. The LM4970 is a feature rich LED driver that is available in a space saving 14 pin non-pullback LLP package.