Rainbow Electronics APR9301 - Manual (Page 5)

INTEGRATED CIRCUITS INC.
- APR9301
http://www.aplusinc.com.tw Page / 10 VER2.1 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