MIC3000 Datasheet, PDF (26/68 Pages) Micrel Semiconductor – SFP Management IC

MIC3000
Alarms and Warning Flags
There are twenty different conditions that will cause the
MIC3000 to set one of the bits in the WARNx or ALARMx
registers. These conditions are listed in Table 17. The less
critical of these events generate warning flags by setting a bit
in WARN0 or WARN1. The more critical events cause bits to
be set in ALARM0 or ALARM1.
An event occurs when any alarm or warning condition be-
comes true. Each event causes its corresponding status bit
in ALARM0, ALARM1, WARN0, or WARN1 to be set. This
action cannot be masked by the host. The status bit will
remain set until the host reads that particular status register,
a power on-off cycle occurs, or the host toggles TXDISABLE.
If TXDISABLE is asserted at any time during normal opera-
tion, A/D conversions continue. The A/D results for all param-
eters will continue to be reported. All events will be reported
in the normal way. If they have not already been individually
cleared by read operations, when TXDISABLE is deasserted,
all status registers will be cleared.
Micrel
Control and Status I/O
The logic for the transceiver control and status I/O is shown
schematically in Figure 13. Note that the internal drivers on
RXLOS, RATE_SELECT, and TXFAULT are all open-drain.
These signals may be driven either by the internal logic or
external drivers connected to the corresponding MIC3000
pins. In any case, the signal level appearing at the pins of the
MIC3000 will be reported in the control register status bits.
Note that the control bits for TX_DISABLE and RATE_SELECT
and the status bits for TXFAULT and RXLOS do not meet the
timing requirements specified in the SFP MSA or the GBIC
Specification, revision 5.5 (SFF-8053) for the hardware sig-
nals. The speed of the serial interface limits the rate at which
these functions can be manipulated and/or reported. The
response time for the control and status bits is given in the
“Electrical Characteristics” section.
Event
Temperature high alarm
Temperature low alarm
Voltage high alarm
Voltage low alarm
TX bias high alarm
TX bias low alarm
TX power high alarm
TX power low alarm
RX power high alarm
RX power low alarm
Temperature high warning
Temperature low warning
Voltage high warning
Voltage low warning
TX bias high warning
TX bias low warning
TX power high warning
TX power low warning
RX power high warning
RX power low warning
Condition
TEMP > TMAX
TEMP < TMIN
VIN > VMAX
VIN < VMIN
IBIAS > IBMAX
IBIAS < IBMIN
TXOP > TXMAX
TXOP < TXMIN
RXOP > RXMAX
RXOP < RXMIN
TEMP > THIGH
TEMP < TLOW
VIN > VHIGH
VIN < VLOW
IBIAS > IBHIGH
IBIAS < IBLOW
TXOP > TXHIGH
TXOP < TXLOW
RXOP > RXHIGH
RXOP < RXLOW
Table 17. MIC3000 Events
MIC3000 Response
Set ALARM0[7]
Set ALARM0[6]
Set ALARM0[5]
Set ALARM0[4]
Set ALARM0[3]
Set ALARM0[2]
Set ALARM0[1]
Set ALARM0[0]
Set ALARM1[7]
Set ALARM1[6]
Set WARN0[7]
Set WARN0[6]
Set WARN0[5]
Set WARN0[4]
Set WARN0[3]
Set WARN0[2]
Set WARN0[1]
Set WARN0[0]
Set WARN1[7]
Set WARN1[6]
M9999-101204
26
October 2004