The TPA711 is a bridge-tied load (BTL) or single-ended (SE) audio power amplifier developed especially for low-voltage applications where internal speakers and external earphone operation are required. Operating with a 3.3-V supply, the TPA711 can deliver 250-mW of continuous power into a BTL 8- load at less than 0.6% THD+N throughout voice band frequencies. Although this device is characterized out to 20 kHz, its operation is optimized for narrower band applications such as wireless communications. The BTL configuration eliminates the need for external coupling capacitors on the output in most applications, which is particularly important for small battery-powered equipment. A unique feature of the TPA711 is that it allows the amplifier to switch from BTL to SE _on the fly_ when an earphone drive is required. This eliminates complicated mechanical switching or auxiliary devices just to drive the external load. This device features a shutdown mode for power-sensitive applications with special depop circuitry to eliminate speaker noise when exiting shutdown mode. The TPA711 is available in an 8-pin SOIC and the surface-mount PowerPAD MSOP package, which reduces board space by 50% and height by 40%.
