LMV1091TM/NOPB National Semiconductor, LMV1091TM/NOPB Datasheet

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... The dual microphone inputs and the processed signal output are differential to provide excellent noise immunity. The mi- crophones are biased with an internal low-noise bias supply. System Diagram © 2011 National Semiconductor Corporation LMV1091 Key Specifications ■ Far Field Noise Suppression Electrical * ■ ...

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Typical Application FIGURE 1. Typical Dual Microphone Far Field noise Cancelling Application www.national.com 2 30092215 ...

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Connection Diagrams 25–Bump micro SMD Marking Top View X = Plant Code YY = Date Code TT = Die Traceability ZA4 = LMV1091TM Order Number Package Drawing Number LMV1091TM 25 Bump µSMD TMD25AAA LMV1091TMX 25 Bump µSMD TMD25AAA 25ump micro ...

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Bump Number Pin Name A1 MIC BIAS A2 MIC2+ A3 MIC2– A4 MIC1+ A5 MIC1– B1 MODE0 B2 MODE1 B3 GA0 B4 GA1 B5 GND C1 MUTE2 C2 GB0 GA2 C5 REF D1 MUTE1 D2 GB1 D3 ...

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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage Storage Temperature Power Dissipation (Note 3) ESD Rating (Note 4) ESD Rating (Note 5) CDM Junction Temperature (T ) JMAX Electrical Characteristics 3.3V Unless otherwise specified, all limits guaranteed for T 20dB, Post Amp gain = 6dB 100kΩ ...

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I Shut Down Current SD T Turn-On Time (Note Turn-Off Time (Note 9) OFF V Logic High Input Threshold IH V Logic Low Input Threshold IL Electrical Characteristics 5.0V Unless otherwise specified, all limits guaranteed for T ...

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Symbol Parameter V Logic High Input Threshold IH V Logic Low Input Threshold IL Note 1: “Absolute Maximum Ratings” indicate limits beyond which damage to the device may occur, including inoperability and degradation of device reliability and/or performance. Functional operation ...

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Test Methods FAR FIELD NOISE SUPPRESSION (FFNS For optimum noise suppression the far field noise should broadside array configuration from the two microphones (see Figure 8). Which means the far field sound source is equidistance from the ...

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Measuring Noise and SNR The overall noise of the LMV1091 is measured within the fre- quency band from 10Hz to 22kHz using an A-weighted filter. For the signal to noise ratio (SNR) the signal level at the out- put is ...

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Typical Performance Characteristics = 18mV , f = 1kHz, pass through mode, Pre Amp gain = 20dB, Post Amp gain = 6dB, R P-P THD+N vs Frequency Mic1 = AC GND, Mic2 = 36mV Noise Canceling Mode THD+N vs Frequency ...

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THD+N vs Input Voltage f = 1kHz Mic1 Pass Through Mode PSRR vs Frequency Pre Amp Gain = 20dB, Post Amp Gain = 6dB V = 100mV , Mic1 = Mic2 = AC GND RIPPLE P-P Mic1 Pass Through Mode ...

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Signal-to-Noise Ratio Electrical vs Frequency 12 30092269 ...

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Application Data INTRODUCTION The LMV1091 is a fully analog single chip solution to reduce the far field noise picked up by microphones in a communi- FIGURE 3. Simplified Block Diagram of the LMV1091 The output signal of the microphones is ...

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Example 1 An application using microphones with 50mV output voltage, and a baseband chip after the LMV1091 with 1.5V maximum input voltage. P-P For optimum noise performance, the gain of the input stage should be set to the maximum. 1. ...

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Pre-Amp/Post-Amp Gains The Pre-amplifier gain of the LMV1091TM can be controlled using the GA0-GA3 pins. See table 2 below for Pre-amplifier GA3 GA2 ...

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Mute Section Mic 1 and Mic 2 can be muted independently, using the Mute 1 and Mute 2 pins. See Table 5 for control settings. Mute Microphone Placement Because the LMV1091 is a microphone array ...

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Low-Pass Filter At The Output At the output of the LMV1091 there is a provision to create order low-pass filter (only enabled in 'Noise Cancelling' mode). This low-pass filter can be used to compensate for the change ...

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Revision History Rev Date 1.0 10/28/09 1.01 05/17/10 1.02 01/13/11 www.national.com Description Initial released. Changed the unit measure of the X1, X2, and X3 (under the Physical Dimension) from mm to μm. Fixed typos on Figure 1 (Typical Application diagram). ...

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Physical Dimensions inches (millimeters) unless otherwise noted 25 Bump micro SMD Technology NS Package Number TMD25AAA = 2015μm = 2015μ 600μ www.national.com ...

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