The TB2902H is a class AB power amplifier with an integrated self-diagnosis function that can be controlled via an I2C bus. Diagnostic capabilities cover turn-on and permanent faults in power amplifier or line driver modes, and can be used during vehicle assembly and for maintenance during its lifetime. Available diagnostic tests include output short detection and offset detection, as well as open circuit detection on vehicle loudspeakers. An automatic tweeter test with selectable 300mA or 500mA current thresholds is also provided. The integration of an I2C capability also allows the amplifier audio controls such as standby, mute and voltage gain to be operated via the bus. It offers a number of built-in protection features including thermal shut down and over voltage protection.