The uA2203A is a stereo audio power amplifier, which combines a bridged-tied load (BTL) mode for speaker and a single end (SE) mode for headphone, specifically designed for LCD monitor and NB. It provides DC volume control which is from 20dB (DC_Vol = 0V) to -80dB (DC_Vol = 3.54V) with 32 steps. The advanced DC volume control minimizes external components.
To simplify design, the speaker volume level is adjusted by applying a dc voltage to the VOLUME terminal. Likewise, the delta between speaker volume and headphone volume can be adjusted by applying a dc voltage to the VOLMAX terminal to avoid an unexpected high volume level through
The uA2203A is capable of continuously delivering 1.25 watts averaged power to an 8 ohm BTL load and 2 watts averaged power to a 4 ohm BTL load with less than 1% distortion from a 5V supply input.
The uA2203A includes shutdown function to reduce the current consumption down to less than 1uA in shutdown mode. A pop & click circuitry is included for eliminating speaker noise during turn on/off transition.
Other features include internal thermal shutdown protection, output short circuit protection and input under voltage lockout. The uA2203A is available in DIP-16L package.