INTEGRATED CIRCUITS INC.

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APR9301

http://www.aplusinc.com.tw

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VER2.3

5

Figure 4 shows the same application using external microphone biasing instead of the

microphone amplifier on the APR9301 device, thus bypassing the preamplifier portion

of the chip function.

Figure 4 Sample Application Using External Microphone Biasing :

Notes:

NC=No Connect (must be floating).

Pins 23 and 27 have internal pull-up resistors.

The typical sampling frequency is 6.4kHz with OscR=52kΩ

NPN bipolar transistor,T1 model #MPS3904 or equivalent.

Electrical Characteristics

Tables 2 through 4 list Absolute Maximum Ratings, Recommended DC Characteristics,

and recommended Analog Characteristics for the APR9301 device