Data Sheet

ADMP510

Rev. 0 | Page 7 of 12

APPLICATIONS INFORMATION

INTERFACING WITH ANALOG DEVICES CODECS

The output of the ADMP510 can be connected to a dedicated

codec microphone input (see Figure 11) or to a high input

impedance gain stage (see Figure 12). A 0.1 µF ceramic capacitor

placed close to the ADMP510 supply pin is used for testing and

is recommended to adequately decouple the microphone from

noise on the power supply. A dc blocking capacitor is required

at the output of the microphone. This capacitor creates a high-

pass filter with a corner frequency at

where R is the input impedance of the codec.

A minimum value of 2.2 μF is recommended in Figure 11

because the input impedance of the ADAU1761/ADAU1361

can be as low as 2 kΩ at its highest PGA gain setting, which

results in a high-pass filter corner frequency at about 37 Hz.

ADAU1761

OR

ADAU1361

ADMP510

GND

OUTPUT

LINN

LINP

MICBIAS

CM

2.2µF

MINIMUM

0.1µF

Figure 11. ADMP510 Connected to the ADAU1761 or ADAU1361 Codec

Figure 12 shows the ADMP510 connected to an ADA4075-2

op amp configured as a noninverting preamplifier.

GAIN = (R1 + R2)/R1

ADMP510

GND

OUTPUT

1µF

MINIMUM

0.1µF

10kΩ

R1

R2

ADA4075-2

Figure 12. ADMP510 Connected to the ADA4075-2 Op Amp

SUPPORTING DOCUMENTS

For additional information, see the following documents.

Evaluation Board User Guide

UG-325, Analog Output MEMS Microphone Flex Evaluation

Board

Circuit Note

CN-0207, High Performance Analog MEMS Microphone’s Simple

Interface to SigmaDSP Audio Codec

Application Notes

AN-1003, Recommendations for Mounting and Connecting

the Analog Devices, Inc., Bottom-Ported MEMS Microphones

AN-1068, Reflow Soldering of the MEMS Microphone

AN-1112, Microphone Specifications Explained

AN-1124, Recommendations for Sealing Analog Devices, Inc.,

Bottom-Port MEMS Microphones from Dust and Liquid Ingress

AN-1140, Microphone Array Beamforming

AN-1165, Op Amps for MEMS Microphone Preamp Circuits

AN-1181, Using a MEMS Microphone in a 2-Wire Microphone

Circuit