AK2540 Datasheet, PDF (21/33 Pages) Asahi Kasei Microsystems – Quad T1 Transceiver

ASAHI KASEI
[AK2540]
Driver Failure Monitor (Hardware Mode and Host Mode)
Driver Failure Monitor asserts the detection of consecutive space or line short.
When DPMx is set “high” or line short circuit in channel x is detected, DFMx(Driver Failure
Monitor) register is set “high” and DFMx pin becomes “high”. INT pin becomes “high” when
DFMx is set “high” if MDFMx is “low”. DFMx registers and DFMx pins represent the current
status regardless of the MDFMx status.
Loss of signal (Hardware Mode and Host Mode)
The receiver will indicate loss of signal upon receiving 175 consecutive zeros (DLOS) or detecting
input level being below the threshold (ALOS).
LOSx returns to “low” when the received signal returns to 12.5% ones density and not including
100 consecutive zeros. (GR-820)
When Loss of Signal is detected in channel x, LOSx register is set “high” and LOSx pin becomes
“high”. When LOSx is set “high”, interrupt will be issued on INT pin if MLOSx is “low”. LOSx
pin becomes high regardless of MLOSx status. MLOSx is active-high and masks LOSx interrupt.
LOSx registers and LOSx pins represent the current status of received signal regardless of the
MLOSx status.
There are also ALOSx registers and the current status of each channel is available.
Loss of TCLK (Host Mode Only)
Loss of TCLKx is reported by setting LOTCx “high”. When LOTCx is set “high”, INT output
becomes “high” if MLOTCx is “low”. MLOTCx is active-high and masks LOTCx interrupt.
LOTCx represents the current status of TCLKx and can be read regardless of MLOTCx status.
When Loss of TCLKx is detected, TTIPx/TRINGx will be forced to “0”(except Remote loopback and
AIS), and AIS in channel x is sent synchronized with MCLK if AISx is selected.
INT_LOMC output (Hardware Mode and Host Mode)
In Host Mode, INT_LOMC(Interrupt Output) output becomes “high” when the alarm is reported at
any one of ALOSx, LOSx, LOTCx, DFMx or DPMx registers. INT_LOMC pin can be masked by
MALOSx, MLOSx, MLOTCx, MDFM or MDPM registers.
In Hardware Mode, INT_LOMC pin assert LOMC(Loss of MCLK alarm).
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