Continued from preceding page.
Pin No. Pin Name DC voltage
AC voltage
16
MIC GND
0V
17
MIC IN
1.64V Reference input level
=-69dBV
LA74303FN
Description of functions
For MIC Amp blocking GND pin
MIC input pin
Maximum input level
=-30dBV
18
MIC VCC
2.30V
MIC power pin
Equivalent circuit diagram in pin
VCCA(=3.0V)
500Ω
17
70kΩ
VREFL
VCCA(=3.0V)
2.2kΩ
18
23kΩ
19
VREFL
2.30V
20
SP GND
0V
24
21
SPK OUT+
1.27V At PB reference input
Output level = -8dBV
(EVR MAX)
22
VCCSP
3.3V
MIC VCC and VREFL ripple
rejection pin
VCCA(=3.0V)
400Ω
19
500Ω
200kΩ
Speaker GND pin
Speaker positive-phase output
pin
Speaker power pin
VCCSP(=3.3V)
10kΩ
21
10.7kΩ
23
No.A1181-12/18