HFE419x-441 Product Specification – Apr 2013 F i n i s a r
Confidential and Proprietary © 2012 Finisar Corporation. All rights reserved Rev. A1 Page 4
Notes:
1. Reliability is a function of temperature, see www.finisar.com 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 ΔP
O
/ΔI
F
.
5. To compute the value of Slope Efficiency at a temperature T, use the following equation:
η(T) ≈ η(25
o
C)*[1+(Δη/Δ 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
(25
o
C)*[1+(ΔR
S
/ ΔT)*(T-25)]
8. Monitor current tracking is defined as follows:
III. 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.
Temperature
Threshold Current
T
MIN
, I
MIN
I
TH
≈
I
MIN
[1.1×10
-4
(T-T
MIN
)
2
+1]
rr
n
Pmax
Typical operating current / power
I
th
η
0.45mW / 0.45mW) (PI
0.75mW / 0.75mW) (PI
Deltrk
OPD
OPD
=
=
=
