Finisar HFE4190-441 User Manual
HFE419X-441 2.5GBPS 850NM VCSEL
NOTES
1.
Reliability is a function of temperature, see
www.finisar.com/aoc.php for details.
2.
For the purpose of these tests, I
F
is DC current.
3.
Threshold current varies as (T
A
– T
O
)
2
. It may either
increase or decrease with temperature, depending upon
relationship of T
A
to T
O
. The magnitude of the change is
proportional to the threshold at T
O
.
4.
Slope efficiency is defined as
∆P
O
/
∆I
F
.
5.
To compute the value of Slope Efficiency at a temperature
T, use the following equation:
η(T) ≈ η(25oC)*[1+(∆η/∆T)*(T-25)]
6.
Rise and fall times specifications are the 20% - 80%. Most
of the devices will measure <135ps fall time. Rise and fall
times are sensitive to drive electronics..
7
To compute the value of Series Resistance at a
temperature T, use the following equation:
R
S
(T)
≈ R
S
(25oC)*[1+
∆R
S
/
∆T)*(T-25)]
8.
Monitor current tracking is defined as follows:
TYPICAL PERFORMANCE CURVES
Emitted Power vs. Current: Power varies approximately
linearly with current above threshold.
Threshold Current vs. Temperature: Threshold current varies
parabolically with temperature; thus it can be nearly constant
for a limited temperature range.
Current
Emitted Power
Pmax
Typical operating current / power
Ith
η
Threshold Current
Temperature
T
MIN
, I
MIN
I
TH
I
MIN
[1.1×10
-4
(T-T
MIN
)
2
+1]
0.45mW
/
0.45mW)
(P
I
0.75mW
/
0.75mW)
(P
I
Deltrk
O
PD
O
PD
=
=
=