msm7602 Oki Semiconductor, msm7602 Datasheet - Page 24

• Manufacturer Part Number: msm7602
• Description: Echo Canceler
• Manufacturer: Oki Semiconductor

¡ Semiconductor
NOTES ON USE
1. Set echo return loss (ERL) to be attenuated. If the echo return loss is set to be
2. Set the level of the analog input so that the PCM CODEC does not overflow.
3. The recommended input level is –10 to –20 dBm0. Refer to the characteristics
4. Applying the tone signal to this echo canceler for long duration may decrease echo
5. For changes in the echo path (retransmit, circuit switching during transmission, and
6. When turning the power ON, set the PWDWN pin to "1" and input the basic clock
7. After powering ON, be sure to reset.
8. After the power down mode is released (when the PWDWN pin is changed to "H"
9. If this canceler is used to cancel acoustic echoes, an echo attenuation may be less
amplified, the echo can not be eliminated.
Refer to the characteristics diagram for ERL vs. echo attenuation quantity.
diagram for the RIN input level vs. echo attenuation quantity.
attenuation.
When used with the HD pin "L" (howling detector ON), this echo canceler may
operate faultily if, while a signal is input to the RIN pin, a tone signal with a higher
level than the signal being input to RIN is input to the SIN pin.
A signal should therefore be input either to the RIN pin or to the SIN pin. If,
however, the tone signal is input to the SIN pin while a signal is input to the RIN pin,
the ADP, HD, or HCL pin must be set to "H".
so on), convergence may be difficult.
Perform a reset, to make it converge.
If the state of the echo path changes after a reset, convergence may again be difficult.
In cases such as a change in the echo path, perform a reset each time.
simultaneously with power ON.
If powering down immediately after power ON, be sure fast input 10 or more clocks
of the basic clock.
from "L"), be sure to reset the device.
than 30 dB.
MSM7602
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