HFE4094-542 Product Specification – Aug 2014
F i n i s a r
Confidential and Proprietary © 2013 Finisar Corporation. All rights reserved Rev. A1 Page 4
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 ∆P
O
/∆I
F
.
5. To compute the value of Slope Efficiency at a temperature T, use the following equation:
η(T) ≈ η(25
o
C)*[1+(∆η/∆ T)*(T-25)]
6. Rollover is the power at which a further current increase does not result in a power increase.
7. 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.
8. To compute the value of Series Resistance at a temperature T, use the following equation:
R
S
(T) ≈ R
S
(25
o
C)*[1+(∆R
S
/ ∆T)*(T-25)]
9. Beam divergence is defined as the total included angle between the 1/e
2
intensity points.
10. These specifications are for the TO-46 component alone. Reflections introduced by any
subsequent higher level assembly may affect these values.
11. 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.
T e m p e r a tu re
Threshold Current
T
M IN
, I
M IN
I
T H
≈
≈ ≈
≈
I
M IN
[1 . 1 × 1 0
- 4
(T -T
M I N
)
2
+ 1 ]
0.45mW / 0.45mW) (PI
0.75mW / 0.75mW) (PI
Deltrk
OPD
OPD
=
=
=
Pmax
Typical operating current / power
I
th
η
