M02069 Datasheet, PDF (34/44 Pages) M/A-COM Technology Solutions, Inc. – 3.3 or 5 Volt VCSEL/FP Laser Driver IC for Applications to 4.3 Gbps

M02069 Data Sheet
3.5
Fault Conditions
This section describes the M02069 operating modes during fault conditions. Over voltage, under voltage, pins
shorted to V_CC 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 Circuit Response to Under-Voltage Condition or Short
to V_CC
to Ground
V_CC
Bias and modulation outputs are disabled once V_CC rises
Bias and modulation outputs are disabled once V_CC drops below
above the supply detection (high voltage) threshold (see
the supply detection (low voltage) threshold
Table 1-3)
DIN+, DIN-
The APC loop will attempt to compensate for the change in The APC loop will attempt to compensate for the change in
output power. If the APC loop can not maintain the set average output power. If the APC loop can not maintain the set average
power, a fault state occurs.^(1,2,3)
power, a fault state occurs.^(1,2,3)
VCC3_SEL
DIS
FAIL
Does not affect laser power.
Bias and modulation outputs are disabled.
SV_CC is opened when CC_SEL is low or floating (or SGND is
opened when CC_SEL is high)
Does not affect laser power.
Does not affect laser power.
Does not affect laser power (normal condition for circuit
operation).
Does not affect laser power.
RESET
Does not affect laser power.
Does not affect laser power.
MOD_MON
BIAS_MON
TxPWR_MON
APC_SET
I_PIN
IBOUT_CA(3)
IBOUT_CC(4)
OUT+⁽³⁾
OUT-⁽⁴⁾
SV_CC(3)
C_APC
V_CC3
Does not affect laser power.
Does not affect laser power.
Does not affect laser power.
Does not affect laser power.
Does not affect laser power.
Does not affect laser power.
A fault state occurs.⁽¹⁾
A fault state occurs.⁽¹⁾
A fault state occurs.⁽¹⁾
A fault state occurs.⁽¹⁾
The laser will be turned off, then a fault state occurs.⁽¹⁾
A fault state occurs.⁽¹⁾
A fault state occurs.⁽¹⁾
The laser will be turned off, then a fault state occurs.⁽¹⁾
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⁾
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.
Does not affect laser power.
Laser bias current will be shut off and a fault state occurs.⁽¹⁾
Laser bias current will be shut off, then a fault state occurs.⁽¹⁾ A fault state occurs.⁽¹⁾
Bias and modulation outputs are disabled once V_CC3 rises
above the supply detection (high voltage) threshold
Bias and modulation outputs are disabled once V_CC3 drops
below the supply detection (low voltage) threshold
PEAK_ADJ
CC_SEL
MOD_SET
Does not affect laser power.
Does not affect laser power
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⁾
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⁾
34
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02069-DSH-001-D
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