MSM7602 Documents
Applications
Description The MSM7602 is a low-power CMOS IC device for canceling echo (in an acoustic
system or telephone line) generated in a speech path.
Echo is canceled, in digital signal processing, by estimating the echo path
and generating a pseudo echo signal.
When used as an acoustic echo canceller, the device cancels the acoustic echo
between the loud speaker and the microphone which occurs during hands free
communication such as with a cellular phone or a conference system phone.
When used as a line echo canceller, the device cancels the line echo caused
by impedance mismatching in a hybrid.
In addition, the MSM7602 makes possible a quality conversation by controlling
the noise level and preventing howling with howling detector, double talk
detector, attenuation function, and a gain control function. The device also
controls the silence level with a center clipping function.
Further, the MSM7602 I/O interface supports µ-law PCM. The use of a single
chip CODEC, such as the MSM7566 (3 V) and MSM7543 (5 V), allows an economic and
efficient echo canceller configuration. |
