LXT350 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation
In Hardware mode, ALOOP becomes active when the LLOOP pin is floating (i.e. Midrange). In
Host mode, setting bit CR2.EALOOP = 1 commands ALOOP. Note that ALOOP overrides all
other loopback modes.
Figure 7. Analog Loopback
2.7.1.3
Remote Loopback (RLOOP)
See Figure 8. When RLOOP is active, the device ignores the transmit data and clock inputs (TCLK
and TPOS/TNEG or TDATA), and bypasses the in-line encoders/decoders. The RPOS/RNEG or
RDATA outputs loop back through the transmit circuits to TTIP and TRING at the RCLK
frequency. The RLOOP command does not affect the receiver circuits which continue to output the
RCLK and RPOS/RNEG or RDATA signals received from the twisted-pair line.
In Host mode, command RLOOP by writing a 1 to bit CR2.ERLOOP. In Hardware mode, RLOOP
is commanded by setting the RLOOP pin High.
Figure 8. Remote Loopback
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Datasheet
ETC [ ETC ]
