msm7617 Oki Semiconductor, msm7617 Datasheet - Page 5

• Manufacturer Part Number: msm7617
• Description: 2-channel Echo Canceler
• Manufacturer: Oki Semiconductor

¡ Semiconductor
PIN DESCRIPTIONS
Pin
1
2
3
4
6
7
8
Symbol
SYNC2
ADP2
RST2
HCL2
NLP2
IOM0
IOM1
Type
I
I
I
I
I
I
Reset signal input pin for channel 2.
Input signals are invalid for 100 ms after reset (after RST returns to "H"
from "L") for setting initial values.
Input the basic clock during reset. Output pins will be placed in the
following states during reset.
AFF coefficient control pin for channel 2.
This pin stops coefficient variation of the adaptive FIR filter (AFF), fixing the
coefficients. It allows once acquired AFF coefficients to be saved.
Echo canceler disable pin for channel 2.
This pin disables the echo canceler and enables data from SIN to SOUT to be output
in "through mode". The input and output levels of SIN and SOUT are changed by the
setting of the SG and SA pins; therefore, to output data from SIN to SOUT in
"through mode", set the SA and SG pins to "0 dB".
It simultaneously clears the adaptive FIR filter coefficients.
Sync signal input pin for channel 2 transmit/receive PCM data while in
parallel I/O mode.
Input the transmit/receive sync signal (8 kHz) of the PCM CODEC connected
to channel 2. Input "L" if not in parallel I/O mode.
NLP control pin for channel 2.
This pin controls center clipping, forcing SOUT2 output to the minimum
positive value when it is below –54 dBm0. It is effective for reducing
uncanceled echoes and low-level noise.
Sets I/O mode of PCM data.
IOM1
"L": Reset
"H": Normal operation
Hi-Z: ROUT2, SOUT2
No effect: SYNCO, SCKO, ROUT1, SOUT1, DF1, WDT1
Previous state: DF2, WDT2
"H": Fixed coefficient mode
"L": Normal mode (variable coefficients)
"H": Disable mode
"L": Normal mode (echo canceller enabled)
"H": Center clipping on
"L": Center clipping off
0
0
1
1
IOM0
0
1
0
1
Mode Setting
2-channel parallel I/O mode
2-channel serial I/O mode
1-channel cross-connected mode
Inhibited
Description
MSM7617
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