Omnidirectional Microphone with Bottom Port and Digital Output Data Sheet ADMP421 FEATURES GENERAL DESCRIPTION Small and thin 3 mm 4 mm 1 mm surface-mount package The ADMP421 is a high performance, low power, digital output High SNR of 61 dBA bottom-ported omnidirectional MEMS microphone. The High sensitivity of 26 dBFS ADMP421 consists of a MEMS microphone element and an Flat frequency response from 100 Hz to 15 kHz impedance converter amplifier followed by a fourth-order - Low current consumption: <650 A modulator. The digital interface allows for the pulse density Sleep mode for extended battery life modulated (PDM) output of two microphones to be time- High PSR of 80 dBFS multiplexed on a single data line using a single clock. Fourth-order - modulator The ADMP421 has a high SNR and high sensitivity, making it Digital PDM output an excellent choice for far field applications. The ADMP421 has Compatible with Sn/Pb and Pb-free solder processes a flat wideband frequency response, resulting in natural sound RoHS/WEEE compliant with high intelligibility. Low current consumption and a sleep mode enable long battery life for portable applications. A built- APPLICATIONS in particle filter provides high reliability. The ADMP421 complies with the TIA-920 Telecommunications Telephone Terminal Smartphones and feature phones Equipment Transmission Requirements for Wideband Digital Teleconferencing systems Wireline Telephones standard. Digital video cameras Bluetooth headsets The ADMP421 is available in a thin 3 mm 4 mm 1 mm Video phones surface-mount package. It is reflow solder compatible with no Tablets sensitivity degradation. The ADMP421 is halide free. FUNCTIONAL BLOCK DIAGRAM ADMP421 CLK PDM ADC MODULATOR DATA POWER CHANNEL MANAGEMENT SELECT Figure 1. Rev. D Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 www.analog.com license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. Fax: 781.461.3113 20102011 Analog Devices, Inc. All rights reserved. OBSOLETE VDD GND L/R SELECT 07596-001ADMP421 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Applications Information .............................................................. 10 Applications ....................................................................................... 1 Interfacing with Analog Devices Codecs ................................ 10 General Description ......................................................................... 1 Sleep Mode .................................................................................. 10 Functional Block Diagram .............................................................. 1 Power Savings When Disabling One Microphone in a Multimicrophone Application .................................................. 10 Revision History ............................................................................... 2 Supporting Documents ............................................................. 10 Specifications ..................................................................................... 3 Handling Instructions .................................................................... 11 Timing Characteristics ................................................................ 4 Pick-and-Place Equipment ....................................................... 11 Absolute Maximum Ratings ............................................................ 5 Reflow Solder .............................................................................. 11 ESD Caution .................................................................................. 5 Board Wash ................................................................................. 11 Pin Configuration and Function Descriptions ............................. 6 Reliability Specifications ................................................................ 12 Typical Performance Characteristics ............................................. 7 Outline Dimensions ....................................................................... 13 PCB Land Pattern Layout ................................................................ 8 Ordering Guide .......................................................................... 13 Alternate PCB Land Patterns ...................................................... 9 REVISION HISTORY 11/11Rev. C to Rev. D 6/11Rev. A to Rev. B Changed PSRR to PSR ....................................................... Universal Changes to Figure 1 ........................................................................... 1 Changed Pb-Free Temperature from 245C to 260C, Table 4 .. 5 Changes to Figure 5 ........................................................................... 7 Changes to Figure 8 and Figure 9 ................................................... 8 Added Alternate PCB Land Patterns Section ............................... 9 2/11Rev. 0 to Rev. A Changes to Temperature Humidity Bias (THB) Description, Changes to Features Section, Applications Section, and Table 6 .............................................................................................. 12 General Description Section ............................................................ 1 Added Dynamic Range Parameter, Changes to Input 8/11Rev. B to Rev. C Characteristics Parameter and Output Characteristics Changes to Clock Frequency and Supply Voltage Parameters, Parameter, Deleted Polarity Parameter, Table 1 ............................ 3 Table 1 ................................................................................................ 3 Changes to Table 3 ............................................................................. 5 Changes to Table 3 and Table 4 ....................................................... 5 Changes to Table 5 ............................................................................. 6 Added Power-Saving Features Section ........................................... 8 Deleted Power-Saving Features Section ........................................ 8 Changes to Figure 9 .......................................................................... 8 Updated Outline Dimensions ....................................................... 13 Added Applications Information Section ..................................... 9 Changes to Ordering Guide .......................................................... 13 Added Supporting Documents, Evaluation Board User Guides, Circuit Note, and Application Notes Sections .............................. 9 4/10Revision 0: Initial Version Changes to Interfacing with Analog Devices Codecs Section ................................................................................................ 9 Moved Sleep Mode Section and Power Savings When Disabling One Microphone in a Multimicrophone Application Section ... 9 Changes to Figure 10 ........................................................................ 9 Change to Pick-and-Place Equipment Section ........................... 10 Deleted Evaluation Board Section ................................................ 10 Deleted Figure 10 and Figure 11 Renumbered Sequentially ... 10 Deleted Table 6 Renumbered Sequentially................................. 10 Deleted Figure 12 ............................................................................ 11 Change to Temperature Cycle Description, Table 6 .................. 11 Changes to Ordering Guide .......................................................... 12 Rev. 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