INMP421

Omnidirectional Microphone with Bottom Port and PDM Digital Output

GENERAL DESCRIPTION

The INMP421 is a high performance, low power, digital

output bottom-ported omnidirectional MEMS microphone.

The INMP421 consists of a MEMS microphone element and an

impedance converter amplifier followed by a fourth-order Σ-Δ

modulator. The digital interface allows for the pulse density

modulated (PDM) output of two microphones to be time-

multiplexed on a single data line using a single clock.

The INMP421 has a flat wideband frequency response,

resulting in natural sound with high intelligibility. Low current

consumption and a sleep mode enable long battery life for

portable applications. A built-in particle filter provides high

reliability. The INMP421 complies with the TIA-920

Telecommunications Telephone Terminal Equipment

Transmission Requirements for Wideband Digital Wireline

Telephones standard.

The INMP421 is available in a thin 3 × 4 × 1 mm surface-

mount package. It is reflow solder compatible with no

sensitivity degradation. The INMP421 is halide free

*Protected by U.S. Patents 7,449,356; 7,825,484; 7,885,423; and 7,961,897.

Other patents are pending.

APPLICATIONS

•

Feature Phones

•

Tablet Computers

•

Teleconferencing Systems

•

Digital Still and Video Cameras

•

Bluetooth Headsets

•

Notebook PCs

•

Security and Surveillance

FEATURES

•

Small and Thin 3 × 4 × 1 mm Surface-Mount Package

•

SNR of 61 dBA

•

Sensitivity of −26 dBFS

•

Flat Frequency Response from 100 Hz to 15 kHz

•

Low Current Consumption: <650 µA

•

Sleep Mode for Extended Battery Life

•

High PSR of 80 dBFS

•

Fourth-order Σ-Δ Modulator

•

Digital PDM Output

•

Compatible with Sn/Pb and Pb-Free Solder Processes

•

RoHS/WEEE Compliant

FUNCTIONAL BLOCK DIAGRAM

ORDERING INFORMATION

PART

TEMP RANGE

INMP421BCEZ-R0*

−40°C to +85°C

INMP421BCEZ-R7†

−40°C to +85°C

EV_INMP421

—

EV_INMP421-FX

—

* – 13” Tape and Reel

† – 7” Tape and reel to be discontinued. Contact sales@invensense.com for

availability.

BOTTOM

TOP

INMP421

ADC

POWER

MANAGEMENT

CLK

DATA

PDM

MODULATOR

CHANNEL

SELECT

InvenSense reserves the right to change the detail

specifications as may be required to permit improvements

in the design of its products.

InvenSense Inc.

1745 Technology Drive, San Jose, CA 95110 U.S.A

+1(408) 988–7339

www.invensense.com

Document Number: DS-INMP421-00

Revision: 1.0.

Release Date: 02/06/2014