4

DS1126DB1

CDB7121P

2 Quick Setup Guide

2 Quick Setup Guide

As a standalone PCB, the CDB7121P can be used in a pressure field acoustic test setup or free field acoustic test setup.

It can also be connected to a compatible codec main board to enable full signal path setup within a system platform.

Acoustic measurements can be obtained using a number of different methods. Typical acoustic test setups, using a

comparison method, are shown in Section 2.1 and Section 2.2.

2.1 Pressure field acoustic test

Recommendations for accurate pressure field measurements are as follows:

•

Ensure calibrated test equipment is used for making measurements

•

Ensure CDB7121P acoustic port hole is tightly sealed within the pressure field test cavity

•

Ensure CDB7121P and reference mic are placed close together with minimum placement error

•

Use a suitable test microphone—a pressure field reference microphone is recommended

•

Ensure the pressure field test cavity is tightly sealed

•

Measurements should be performed within a quiet environment

Figure 2-1. Pressure field test setup with CDB7121P

Pressure Field

Reference Mic

Test

Speaker

Power

Quiet Environment

Sound

Pressure

Level

Standard Test Equipment

Test Point

Connections

Pressure Field Test Cavity

CDB7121P