LMV1089RLEVAL National Semiconductor, LMV1089RLEVAL Datasheet

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... C command logic pin control. 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. © 2010 National Semiconductor Corporation LMV1089 Key Specifications ■  Far Field Noise Suppression (Electrical 1kHz) ■ ...

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Typical Application www.national.com 2 ...

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Connection Diagrams 36–Bump micro SMD Marking Top View X = Plant Code YY = Date Code TT = Die Tracability ZA2 = LMV1089RL 36–Bump micro SMD package Top View Order Number LMV1089RL See NS Package Number RLA36TTA 30047231 3 30047230 ...

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Connection Diagrams 32 Lead LQFP Marking Top View U = Wafer Fab Code Z = Assembly Plant Code Digit Date Code TT = Die Traceability LMV1089 = LMV1089VY Ordering Information Order Number Package LMV1089RL 36 Bump µSMD ...

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Pin Descriptions Bump Number Pin Name A1 NC Auxiliary Control Manual Calibration = MIC2– A5 MIC2+ A6 Mic Bias GND B5 M1_UNP B6 MIC1 ...

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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) Junction Temperature (T ) JMAX Mounting Temperature Infrared or Convection (20 sec.) Electrical Characteristics 3 ...

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V Microphone Bias Supply Voltage BM Microphone Bias Noise Level e VBM I Total available Microphone Bias Current BM I Supply Quiescent Current DDQ I Supply Current DD I Shut Down Current SD Supply Current during Calibration and I DDCP ...

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Electrical Characteristics 5.0V Unless otherwise specified, all limits guaranteed for T Pre Amp gain = 20dB, Post Amp gain = 6dB, R Symbol Parameter SNR Signal-to-Noise Ratio e Input Referred Noise level N V Maximum Input Signal IN Maximum AC ...

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Digital Interface Characteristics Unless otherwise specified, all limits guaranteed for T Symbol Parameter V Logic High Input Level IH V Logic Low Input Level IL ts CAL Setup Time CAL CAL Hold time until calibration is th CAL finished ts ...

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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 15). Which means the far field sound source is equidistance from the ...

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Typical Performance Characteristics = 18mV , f =1 kHz, pass through mode (Note 8), 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 ...

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THD+N vs Input Voltage Mic1 = AC GND 1kHz Mic2 Noise Canceling Mode THD+N vs Input Voltage f = 1kHz Mic1 Pass Through Mode www.national.com THD+N vs Input Voltage Mic2 = AC GND 1kHz Mic1 Noise ...

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PSRR vs Frequency Pre Amp Gain = 20dB, Post Amp Gain = 6dB V = 100mV , Mic1 = Mic2 = AC GND RIPPLE P-P Mic1 Pass Through Mode PSRR vs Frequency Pre Amp Gain = 20dB, Post Amp Gain ...

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Signal-to-Noise Ratio Electrical vs Frequency www.national.com 30047256 14 ...

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Application Data INTRODUCTION The LMV1089 is a fully analog single chip solution to reduce the far field noise picked up by microphones in a communi- FIGURE 4. Simplified Block Diagram of the LMV1089 The output signal of the microphones is ...

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interface (see Table 6) will override this default gain. The default gain is only set during power up of the device. Toggling the logic level of the enable pin (EN) will not change the current ...

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Example 2 An application using microphones with 10mV output voltage, and a baseband chip after the LMV1089 with 3.3V maximum input voltage. P-P For optimum noise performance we would like to have the maximum gain at the input stage. 1. ...

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Register changes take effect at the SCL rising edge during the last ACK from slave write (SDA = “0” read (SDA = “1”) ack = acknowledge (SDA pulled down by slave repeated start When ...

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Symbol 1 Hold Time (repeated) START Condition 2 Clock Low Time 3 Clock High Time 4 Setup Time for a Repeated START Condition 5 Data Hold Time (Output direction, delay generated by LMV1089) 5 Data Hold Time (Input direction, delay ...

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Address Reg. Bits Microphone preamplifier gain from 6dB up to 36dB in 2dB steps. A [3:0] 0x01h A4 = mute mic1 and A5 = mute mic2. A [5: microphone on) Mic enable bits enable Mic1, ...

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Address Reg. Bits [3:0] Control the gain compensation between the two mics at 3kHz 0000 (0) 0001 (1) 0010 (2) 0011 (3) 0100 (4) 0101 (5) 0110 (6) 0111 (7) 1000 (8) 1001 (9) 1010 (A) 1011 (B) 1100 (C) ...

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Address Reg. Bits [3:0] Control compensation gain for left channel at ALL frequencies 0x10h P [7:4] Control compensation gain for right channel at ALL frequencies [6:0] Values are clocked into EEPROM registers once “newdata” pulse is generated StoreBar signal Q ...

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Calibration Automatic calibration should only be required once, when the product containing the LMV1089 has completed manufac- ture, and prior to application packaging. The product contain- ing the LMV1089 will be calibrated to the microphones, the microphone spacings, and the ...

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AUTOMATIC CALIBRATION VIA I To initiate the automatic calibration via the I following procedure is required: • From the initial condition where PE is 'low' level • Bring 'high' level (enable EEprom write) • Write '1' into ...

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PERFORMING A THREE TONE CALIBRATION In a system with two microphones in an enclosure there will always be a difference in the transfer function in both gain and frequency response between the two channels. The LMV1089 has the capability to ...

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AUTOMATIC CALIBRATION SETUP A calibration test setup consists of a test room (acoustical box) with a loudspeaker (acoustical source) driven with the test tone sequence from Figure 12. The test setup is shown in Figure 13. The distances between the ...

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SUPPLY CURRENT DURING CALIBRATION The calibration function performs two main tasks in a se- quence. First the AC characteristics of the microphones are matched. Then in the second stage, if the PE pin is high, the on-chip EEPROM is programmed. ...

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Low-Pass Filter At The Output At the output of the LMV1089 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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FIGURE 17. A-Weighted Filter For the signal to noise ratio (SNR) the signal level at the out- put is measured with a 1kHz input signal of 18mV A-weighted filter. This voltage represents the output voltage of a typical electret condenser ...

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Revision History Rev Date 1.0 09/24/08 Initial release. 1.01 09/30/08 Text edits. 1.02 10/14/08 Text edits. 1.03 10/24/08 Text edits. 1.04 10/28/08 Added the LMV1089VY package . 1.05 12/11/08 Text edits. 1.06 12/17/08 Text edits. 1.07 01/13/09 Edited graphic 30047227 ...

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Physical Dimensions inches (millimeters) unless otherwise noted X = 3.459±0.03(mm 3.459±0.03(mm Bump micro SMD Technology NS Package Number RLA36TTA X = 3.459(mm)±0.03 0.66±0.075(mm Lead LQFP Technology NS Package Number NVBE0032 ...

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