Amp in a microphone

National Semiconductor’s LMV1012 and LMV1014 are claimed to be the market’s first ‘amps in a mic,’ as they can be integrated directly inside 2- and 3-wire electret condenser microphones.

National Semiconductor’s LMV1012 and LMV1014 are claimed to be the market’s first ‘amps in a mic,’ as they can be integrated directly inside 2- and 3-wire electret condenser microphones (ECMs).

As such, the products are suitable for use in mobile handsets, headset accessories and other portable microphone applications.

National Semiconductor’s LMV1012 is an amplifier for 2-wire ECMs. The built-in gain of 17dBV has been optimised for handset microphones. Additional benefits of the LMV1012 are improved RF immunity and low distortion. New ECMs using the LMV1012 offer THD of 0.1%, SNR greater than 55dB and supply current less than 240uA.

The LMV1014, on the other hand, is an amplifier for 3-wire, low current and low noise ECMs. This product draws a supply current of less than 40 microamps while providing a low output impedance of 200 Ohms. The LMV1014 provides a high power supply rejection ratio (PSRR) greater than 60dB and an SNR of greater than 55db.

Both amplifiers are fully compatible with existing ECM standards.

The LMV1012 is available now in 4-bump micro SMD packaging and is priced at $0.39. The LMV1014, available now in 4-bump micro SMD packaging, is priced at $0.49. Both prices are in 1000-unit quantities.