msm7718-01 Oki Semiconductor, msm7718-01 Datasheet - Page 31

• Manufacturer Part Number: msm7718-01
• Description: Echo Canceler With Adpcm Codec
• Manufacturer: Oki Semiconductor

¡ Semiconductor
B3 ... Detection of a call progress tone
B2 ... Detection of a DTMF tone
B1 ... PCMLNI input 2100 Hz tone detection (DET21L: valid only in the line echo canceler
B0 ... PCMACI input 2100 Hz tone detection (DET21A: valid only in the line echo canceler
(9) CR8 (Setting of line echo canceler operating mode)
B7 ... “Through” mode control bit for the line echo canceler.
B6 ... Selects whether or not to clear the coefficient 1 of the adaptive FIR filter (LAFF) used by the
B5 ... Selects whether or not to clear the coefficient 2 of the adaptive FIR filter (LAFF) used by the
B4 ... Howling detector (HD) ON/OFF control
B3 ... Turns ON or OFF the center clip function which forcibly sets the SoutL output of the line echo
B2 ... Selects whether or not to update the coefficient of the adaptive FIR filter (LAFF) for the line echo
B1 ... Turns ON or OFF the ATT function which prevents howling from occurring by means of
B0 ... Turns ON or OFF the gain control function which controls the RinL input level and
CR8
Initial value
*1 Names of control pins used in the MSM7602
In the “Through” mode, RinL and SinL data is output directly to RoutL and SoutL
1: “Through” mode 0: Normal mode (echo cancellation)
1: Resets the coefficient
0: Normal operation
1: Resets the coefficient
0: Normal operation
1: Center clip function ON
0: Center clip function OFF
1: Coefficient fixed mode
0: Normal mode (updates the coefficient)
When a signal is input to RinL only, the attenuator ATTsL of the SoutL output is activated.
1: ATT OFF
0: ATT ON
The gain controller adjusts the RIN level when it is –24 dBm0 or above, and it has the control
1: Gain control ON
0: Gain control OFF
expansion mode)
1: Detected
expansion mode)
1: Detected
respectively.
line echo canceler.
line echo canceler.
canceler to minimum positive value when it is –57 dBm0 or less.
canceler.
attenuators ATTsL and ATTrL provided for the RinL input and the SoutL output of the line
echo canceler.
When a signal is input to SinL only or to both SinL and RinL, the attenuator ATTrL of the
RinL input is activated. Their ATT values are both about 6 dB.
prevents howling from occurring by the gain controller (GainL) for the RinL input of the line
echo canceler.
range of 0 to –8.5 dB.
LECTHR
(HCL)*1
B7
1
0: Not detected
0: Not detected
LECCLR1 LECCLR2
B6
0
B5
0
1: Detected 0: Not detected
1: Detected 0: Not detected
LECHD
B4
0
LECCCLP
(NLP)*1
B3
0
1: ON 0: OFF
(ADP)*1
LECHLD
B2
0
(ATT)*1
LECATT
B1
0
MSM7718-01
(GC)*1
LECGC
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B0
0