Class D Chips Shrink Footprint, Power, Noise

A filter-free stereo class D audio power amp from Texas Instruments maximizes cell-phone talk time and audio quality. With about two-thirds lower quiescent current and 80% lower noise floor than its nearest competitor, the TPA2012D2 is a 2.1-W stereo class D audio power amplifier housed in a 4- by 4-mm ThinQFN. It operates from a 3.3-V supply, draws 6 mA, and has a 27-mV_RMS A-weighted noise floor. Available now, it costs $0.95 in quantities of 1000. A lead-free 2- by 2-mm version in wafer chip-scale packaging is sampling now. Volume quantities ($1.05 in 1000-unit lots) are slated for March.