
μ
PD9903
5
1. PIN FUNCTIONS
Number
Pin Name
I/O
Function
1-10
NC
–
Leave this pin open.
11
AV
DD
–
+5 V power supply (analog)
12
DV
DD1
–
+5 V power supply (digital)
13
DV
DD2
–
+5 V power supply (digital)
14
AUX/MODE
I
External signaling input
15
BSY
O
BUSY LED driver output
16
SUS
O
SUS LED driver output
17
RST
I
Pin for reset input and power-on reset
H: HW
X
valid, L: HW
X
output’s internal F/F clear status
18
EXS
O
SIPO sync signal output for expansion port
Note 1
19
EXD
O
SIPO serial data output for expansion port
Note 1
20
HW
R
I
Reception highway input [PCM data (8-bit) + CTL data (8-bit)]
21
DCLK
I
Clock input (2.048 MHz)
22
FS
I
8-kHz sync input
Rising: HW
R
PCM data input start
Rising: HW
X
PCM data output start
Falling: HW
R
CTL data input start
Falling: HW
X
SCN data output start
23
HW
X
O
Transmission highway output [PCM data (8-bit) + SCN data (8-bit)]
24
TYPE
O
HW
X
data enable
25
RT
IN1
I
Ring-Trip signal input 2
26
RT
IN0
I
Ring-Trip signal input 1
27
RC
3
O
Relay control for network testing
[to the
μ
PC7073’s pin 22]
28
RC
2
O
Relay control for line testing
[to the
μ
PC7073’s pin 21]
29
RC
1
O
Relay control for ringer transmit
[to the
μ
PC7073’s pin 20]
30
BCUT
O
High and wet control output
[to the
μ
PC7073’s pin 19]
31
ALM
O
Control output for ground-fault/power line contact protection mode
[to the
μ
PC7073’s pin 18]
32
PD
O
Power-down control output
[to the
μ
PC7073’s pin 17]
33
DGND2
–
Digital ground 2
Note 2
34
DGND1
–
Digital ground 1
Note 2
35
SUB
–
Substrate ground
Note 2
36
AGND
–
Analog ground
Note 2
37
ACOM
IN
I
Signal ground input
Note 3
[to the
μ
PC7073’s pin 11]
38
ACOM
OUT
O
Signal ground output
Note 3
[to the
μ
PC7073’s pin 11]
39
A
OUT
O
Analog signal output for receive side
[to the
μ
PC7073’s pin 10]
40
A
IN
I
Analog signal input for transmit side
[to the
μ
PC7073’s pin 9]
41
AGDT
I
Tip-Ring sum current detection input
[to the
μ
PC7073’s pin 8]
42
ASCN
I
Tip-Ring difference current detection input
[to the
μ
PC7073’s pin 7]
43
BB
IN
I
V
BB
voltage information input
[to the
μ
PC7073’s pin 6]
Notes 1.
SIPO: Serial In Parallel Out
2.
Short AGND, DGND1, DGND2, and SUB directly under the IC and connect them to an analog ground.
3.
Short ACOM
IN
and ACOM
OUT
directly under the IC.