msm7715 Oki Semiconductor, msm7715 Datasheet - Page 14

• Manufacturer Part Number: msm7715
• Description: Multi-function Telecommunication Lsi
• Manufacturer: Oki Semiconductor

¡ Semiconductor
Modem signal flow
Figure 7 shows the signal flow during normal modem operation.
The MSM7715 uses the analog loopback test (ALB) mode and remote digital loopback test
(RDLB) mode as the modem testing functions. In these test modes, the signal flow shown in
Figure 8 is used. O (originate)/A (answer) in the test mode is the expression based on the
modulator side. In ALB mode, the transmit analog signal is input to the demodulator and can
be monitored as RD. In RDLB mode, the modem is configured as the remote modem in the RDL
test mode.
Data from the other modem that requested for RDL is returned to the other modem as a result
of echo-back.
[ALB]
[RDLB]
Line
AOUT
AIN
AOUT
AIN
AIN
AOUT
Figure 7 Signal Flow in Normal Operation
Figure 8 Signal Flow in Test Mode
Transmit filter
Transmit filter
Receive filter
Transmit filter
Receive filter
Receive filter
Demodulator
Demodulator
Demodulator
Modulator
Modulator
Modulator
RD
TD
RD
TD
RD
TD
Received data
Transmitted data
Received data
Transmitted data
Received data
Transmitted data
MSM7715
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