34 Mindspeed Technologies™ 02069-DSH-001-D
Mindspeed Proprietary and Confidential
M02069 Data Sheet
3.5 Fault Conditions
This section describes the M02069 operating modes during fault conditions. Over voltage, under voltage, pins
shorted to VCC and pins shorted to ground are included in the fault Table 3-3.
Table 3-3. Circuit Response to Single-Point Fault Conditions
Pin Name Circuit Response to Over-voltage Condition or Short
to VCC
Circuit Response to Under-Voltage Condition or Short
to Ground
VCC Bias and modulation outputs are disabled once VCC rises
above the supply detection (high voltage) threshold (see
Table 1-3)
Bias and modulation outputs are disabled once VCC drops below
the supply detection (low voltage) threshold
DIN+, DIN- The APC loop will attempt to compensate for the change in
output power. If the APC loop can not maintain the set average
power, a fault state occurs.(1,2,3)
The APC loop will attempt to compensate for the change in
output power. If the APC loop can not maintain the set average
power, a fault state occurs.(1,2,3)
VCC3SEL Does not affect laser power. Does not affect laser power.
DIS Bias and modulation outputs are disabled.
SVCC is opened when CCSEL is low or floating (or SGND is
opened when CCSEL is high)
Does not affect laser power (normal condition for circuit
operation).
FAIL Does not affect laser power. Does not affect laser power.
RESET Does not affect laser power. Does not affect laser power.
MODMON Does not affect laser power. Does not affect laser power.
BIASMON Does not affect laser power. Does not affect laser power.
TxPWRMON Does not affect laser power. Does not affect laser power.
APCSET A fault state occurs.(1) A fault state occurs.(1)
IPIN A fault state occurs.(1) A fault state occurs.(1)
IBOUTCA(3) The laser will be turned off, then a fault state occurs.(1) A fault state occurs.(1)
IBOUTCC(4) A fault state occurs.(1) The laser will be turned off, then a fault state occurs.(1)
OUT+(3) Laser modulation is prevented; the APC loop will increase the
bias current to compensate for the drop in laser power if it is
DC coupled. If the set output power can not be obtained, a
fault state occurs.(1,2)
A fault state occurs.(1)
OUT-(4) Does not affect laser power during common cathode
operation because output is AC coupled.
Does not affect laser power during common cathode operation
because output is AC coupled.
SVCC(3) Does not affect laser power. Laser bias current will be shut off and a fault state occurs.(1)
CAPC Laser bias current will be shut off, then a fault state occurs.(1) A fault state occurs.(1)
VCC3 Bias and modulation outputs are disabled once VCC3 rises
above the supply detection (high voltage) threshold
Bias and modulation outputs are disabled once VCC3 drops
below the supply detection (low voltage) threshold
PEAKADJ Does not affect laser power. Does not affect laser power
CCSEL Normal operation for common cathode configuration. If the
M02069 is configured for common anode drive, a fault state
will occur.(1)
Normal operation for common anode configuration. If the
M02069 is configured for common cathode drive, a fault state
will occur.(1)
MODSET When the laser is DC coupled in common anode configuration,
the APC loop will attempt to compensate for the drop in output
power. If the APC loop can not maintain the set average
power, a fault state occurs.(1,2)
A fault state occurs.(1)