LMV1022 Datasheet | National Semiconductor

Description The LMV1022 and LMV1023 integrate a pre-amplifier and ADC that can be mounted inside an electret condenser microphone (ECM). The digital output signal is a pulse density modulation (PDM) bitstream that alows the microphone to connect directly to the DSP or baseband processor. Part of National Semiconductor’s Powerwise™ family of products, the LMV1022/LMV1023 consume 900µW of power during operation, offering significant power savings over an analog microphone with an external ADC. The LMV1022 outputs its data on the rising clock edge. The LMV1023 outputs its data on the falling clock edge. Both devices can share the same clock and data lines to create a 4-wire stereo solution. The external clock frequency sets the audio pass band frequency. An 800k Hz clock sets the pass band to 7k Hz. A 2.4MHz clock sets the pass band to 20k Hz. The LMV1022 and LMV1023 are available in 6-bump micro SMD packages with 1kg adhesion properties. Key Specifications (Typical VDD = 1.8V, CLOCK = 1.2MHz, f INPUT = 1k Hz, VINPUT = 18m VPP, unless otherwise specified) - SNR A-weighted 61d B - Analog A-weighted noise floor 5 µVRMS - Supply current 0.5m A - Total harmonic distortion 0.05% - Power supply rejection ratio 87d B Features - Integrated 21 d B Pre-Amp and ADC for significant power and space savings - Integrated high-pass Filter to reduce 'Plop Noise' - Excellent RF immunity (e.g. buzz noise) - LMV1022 and LMV1023 bine to create 4-wire Stereo Solution - Very thin 0.35mm micro SMD packaging - Adhesion technology >1kg Applications - Digital audio subsystems and stereo arrays - Electret condenser microphones with all digital output - Portable munications and small form factor devices - Digital audio puting or voice security - Automotive or array systems - Headphone and headset accessories Typical Application For a stereo application, see STEREO OPERATION in the Application Section. © 2011 National Semiconductor Corporation 202124 202124 Version 2 Revision 1...