M02061 Datasheet, PDF (31/37 Pages) M/A-COM Technology Solutions, Inc. – 3.3 or 5 Volt Laser Driver

Functional Description
T_ONE-SHOT = 3 ms + (0.3 ms/pF) x (external capacitance).
Figure 3-8. Safety Circuit Block Diagram, for SCB Pin Low
DIS
If chip is ‘healthy’, then Enable the
outputs and Start 3msec Reset
AND
AND
Pulse(one-shot)
AND
VccOK Detection:
5v Mode:
AND
Latch for
CrudeFaults
SRlatch
R: eset
Q
Vcc Pin
5v Hi/Lo Limits
Set
_
Vcc3 Pin
AND
3.3v Hi/Lo Limits
Latch for
Bias_OK
VCC_OK
ONE-SHOT:
Start
OR
SRlatch
3.3v Mode:
t=0
3ms + Tcap ^PULSE
R: eset
Q
Vcc Pin
5v Hi/Lo Limits
Vcc3 Pin
‘1’
AND
RESET
NOTE: Pulse stays high
if Reset pin is GNDed.
Set
_
optional cap for longer T_init
3.3v Hi/Lo Limits
CrudeFaults Detection:
OutP
Capc
MODset
IBout
> 300mV
> 300mV
> 300mV
> 300mV
CrudeFaults_OK
BiasOK Detection:
Window Compare:
HI Limit
MPCset
LOW Limit
OR
BIAS_OK
OUTPUT_ENABLE
FAILout
(open-collector)
3.5
Fault Conditions when SCB is Low
This section describes the M02061 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.
Table 3-3. Circuit Response to Single-point Fault Conditions, when SCB is Low ^{1 2} (1 of 2)
Pin Name
Circuit Response to Over-voltage Condition
or Short to V_CC
Circuit Response to Under-Voltage Condition
or Short 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
the supply detection (low voltage) threshold
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)}
power, a fault state occurs.^{(1, 2)}
VCC3_SEL
Does not affect laser power.
Does not affect laser power.
02061-DSH-001-G
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