The AAP803AX ECM microphone preamplifier is a chip-scale device developed specifically for integrating in small form factor two terminal electret condenser microphones. The AAP803Ax preamplifier provides reduced input capacitance, improved noise performance and larger output swing at a lower supply voltage. The AAP803Ax is offered in two versions with the part numbers AAP803A1 and AAP803A3. The AAP803A1 has 3 gain settings (low, mid and high and the A3 has 2 gain settings (mid and max) both are designed with low quiescent current consumption for use in lower power typically battery powered applications. The gain setting is done by selecting the proper FB pin for the signal path (1, 2, or 1 and 2). The AAP803Ax is provided in a chip scale SMD package. The package size is 820µm x 550µm; with an overall height of 315µm including solder bumps. This extremely small package size and aspect ratio is optimum for use in small diameter microphones.