AN-000048
PDM Digital Output MEMS Microphone Flex Evaluation Board
User Guide
GENERAL DESCRIPTIONTABLE 2. MICROPHONE FUNCTIONAL DIFFERENCES

This user guide applies to the following MEMS microphoneevaluation boards:

Mics are bottom port unless specified otherwise
Maximum
SupplyMicrophone Current
Sensitivity
Clock Frequency

•••
•
•••
•
•

EV_ICS-41350-FX
EV_ICS-41351-FX
EV_ICS-51360-FX
EV_INMP421-FX
EV_INMP521-FX
EV_INMP522-FX
EV_INMP621-FX
EV_T3902-FX
EV_T5818-FX

ICS-41350
0.65 mA
ICS-41351

This is a simple evaluation board that allows quick evaluationof the performance of PDM MEMS microphones. The small
size and low profile of the flexible PCB enables direct
placement of the microphone into a prototype or an existing
design for an in situ evaluation. The evaluation board consistsof a bottom port microphone soldered to a flexible PCB withcolor-coded wires attached. The only other component on theboard is a 0.1μF supply bypass capacitor.
Table 1 describes the functions of the five connection wires.
Table 2 describes the functional differences between thedifferent microphones that are used with this flex circuit.

400 kHz to 3.3 MHz−32 dB FS

4.1 to 4.8 MHz−26 dB FS

690 kHz to 2.65 MHz(Top port)

0.6mA−35.5 dB FS

2.97 to 3.6 MHz

ICS-51360

0.59mA−26 dB FS

690 to 800 kHz−36 dB FS

1.0 to 4.8 MHz

INMP4210.65 mA−26 dB FS

1.0 to 3.3 MHz

INMP521

1.2 mA−26 dB FS

1.25 to 3.072 MHz

INMP522

1.2 mA−26 dB FS

0.9 to 3.6 MHz

INMP621

1.3 mA−46 dB FS

0.9 to 3.6 MHz−26 dB FS

400 kHz to 3.3 MHz−32 dB FS

4.1 to 4.8 MHz-26 dB FS

400 to 800 kHz-41 dB FS

2.0 to 3.3 MHz

T3902
0.65 mA
T5818
0.59 mA

TABLE 1. PIN FUNCTION DESCRIPTIONS−26 dB FS

EVALUATION BOARD CIRCUIT

Wire
Color

MicrophonePin

Description

Blue

DATA

PDM digital output signal

Red

VDD

Power supply, 1.62 V to 3.63 V DC

White

CLK

Clock input

Black

GND

GroundYellow

L/R SELECT

Left /right channel selectFigure 1 shows the schematic of the evaluation boards; Figure
2 (EV_ICS-41350-FX),
Figure 3 (all other bottomport) and Figure 4 (EV_ICS-41351-FX) show the flex board
layouts. See the respective microphone data sheets forcomplete descriptions and specifications of the microphones.
RED: VDD

U1
MICROPHONE
WHITE: CLK

DATA1 (right): L/R SELECT tied to
GND

YELLOW:
L/R SELECT

1 CLK
2VDD

4

L/R SELECTDATA 5GND
3

DATA2 (left): L/R SELECT pulled to
VDD

BLUE: DATABLACK: GND

Figure 1. Evaluation Board Schematic

InvenSense reserves the right to change the detailspecifications 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: AN-000048
Revision: 1.2
Release Date: 6/1/2020

C10.1µF

AN-000048

Figure 2. EV_ICS-41350-FX Board Layout (Top View)

Figure 3. Bottom Port Mic Evaluation Board Layout (Top View)

Figure 4. EV_ICS-41351-FX Board Layout (Top View)

3.60

12.00

Figure 5. Bottom Port Evaluation Board

Figure 6. Top Port Evaluation Board

Dimensions in Millimeters (Wires Not Included)

EVALUATION BOARD PHOTOGRAPHSFigure 7. EV_ICS-41350-FX Top View

Figure 8. Bottom Port Mic Top and Bottom View (All Others)

Figure 9. EV_41351-FX Top View

Document Number: AN-000048
Revision: 1.2

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AN-000048
REVISION HISTORYREVISION DATEREVISIONDESCRIPTION

3/11/2015

1.0

Initial Release

1/25/2016

1.1

Added EV_ICS-41350-FX

6/1/2020

1.2

Added EV_ICS-41351-FX, EV_ICS-51360-FX, EV_T3902FX, EV_T5818-FX

Document Number: AN-000048
Revision: 1.2

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AN-000048
COMPLIANCE DECLARATION DISCLAIMERInvenSense believes the environmental and other compliance information given in this document to be correct but cannot
guarantee accuracy or completeness. Conformity documents substantiating the specifications and component characteristics are onfile. InvenSense subcontracts manufacturing, and the information contained herein is based on data received from vendors andsuppliers, which has not been validated by InvenSense.

This information furnished by InvenSense, Inc. (“InvenSense”) is believed to be accurate and reliable. However, no responsibility is assumed by InvenSense for its use,or for any infringements of patents or other rights of third parties that may result from its use. Specifications are subject to change without notice. InvenSense reserves
the right to make changes to this product, including its circuits and software, in order to improve its design and/or performance, without prior notice. InvenSense makes
no warranties, neither expressed nor implied, regarding the information and specifications contained in this document. InvenSense assumes no responsibility for any
claims or damages arising from information contained in this document, or from the use of products and services detailed therein. This includes, but is not limited to,claims or damages based on the infringement of patents, copyrights, mask work and/or other intellectual property rights.
Certain intellectual property owned by InvenSense and described in this document is patent protected. No license is granted by implication or otherwise under any
patent or patent rights of InvenSense. This publication supersedes and replaces all information previously supplied. Trademarks that are registered trademarks are theproperty of their respective companies. InvenSense sensors should not be used or sold in the development, storage, production or utilization of any conventional ormass-destructive weapons or for any other weapons or life threatening applications, as well as in any other life critical applications such as medical equipment,
transportation, aerospace and nuclear instruments, undersea equipment, power plant equipment, disaster prevention and crime prevention equipment.
©2020 InvenSense. All rights reserved. InvenSense, MotionTracking, MotionProcessing, MotionProcessor, MotionFusion, MotionApps, DMP, AAR, and the InvenSense
logo are trademarks of InvenSense, Inc. The InvenSense logo is a trademark of InvenSense Corporation. Other company and product names may be trademarks of therespective companies with which they are associated.

©2020 InvenSense. All rights reserved.

Document Number: AN-000048
Revision: 1.2

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