µ
PD9930
Table 1-1 List of Pin Functions (2/2)
Pin No.
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
Pin Name
XAUXI–
XACOMI
XACOMO
RACOMO
RACOMI
REC2O+
REC2O–
IC
REC2I–
REC1O
RAUXO
AV
DD1
AV
DD2
DV
DD
SEN
SI
SO
SCLK
TEST
MSTR
Input/Output
Input
Input
Output
Output
Input
Output
Output
—
Input
Output
Output
—
—
—
Output
Input
Output
Output
Input
Input
Digital power. Connect to a digital power supply line near
µ
PD9930 pins.
DSP interface enable signal output
DSP interface serial input
DSP interface serial output
DSP interface clock output (256 kHz)
Set at high level
Microcontroller interface strobe signal input
Function
Accessory input amplifier inverted input
Voice send internal reference voltage input
Voice send internal reference voltage (1.2 V) output
Voice receive internal reference voltage (1.2 V) output
Voice receive internal reference voltage input
Receiver amplifier 2 non-inverted output
Receiver amplifier 2 inverted output
Internal connection; leave unconnected
Receiver amplifier 2 inverted input
Connect sidetone gain adjust resistor.
Receiver amplifier 1 output
Accessory output amplifier output
Analog power. Connect to an analog power supply line near
µ
PD9930 pins.
Caution Short-circuit the XACOMI and XACOMO pins at a location as close to the pins of the
µ
PD9930 as
possible. Connect a capacitor (chip capacitor or electrolytic capacitor) between this short-circuited
portion and analog ground.
The same applies to the RACOMI and RACOMO pins.
The transmission/reception level is determined by these reference pins. Therefore, make sure that
these pins are not affected by noise or fluctuation of ground potential due to current.
7
NEC [ NEC ]
