The TPA0243 is a 2-W mono bridge-tied-load (BTL) amplifier designed to drive speakers with as low as 4- impedance. The mono signal is created by summing left and right inputs. The amplifier can be reconfigured on the fly to drive two stereo single-ended (SE) signals into headphones. This makes the device ideal for small notebook computers, PDAs, digital personal audio players, anyplace a mono speaker and stereo headphones are required. From a 5-V supply, the TPA0243 can deliver 2 W of power into a 4- speaker. The gain of the input stage is set by the user-selected input resistor and a 50-k internal feedback resistor (AV = RF/ RI). The power stage is internally configured with a gain of 1.25 V/V in SE mode, and 2.5 V/V in BTL mode. Thus, the overall gain of the amplifier is 62.5 k/ RI in SE mode and 125 k/ RI in BTL mode. The input terminals are high-impedance CMOS inputs, and can be used as summing nodes. The TPA0243 is available in the 10-pin thermally-enhanced MSOP package (DGQ) and operates over an ambient temperature range of 40C to 85C.