© 2020
20
PLDXK-CH SERIES LASER DIODE DRIVER
SAFE OPERATING AREA CALCULATION
The Safe Operating Area of the PLDxK-CH driver is
determined by the amount of power that can be dissipated
within the output stage of the driver. If that power limit is
exceeded, permanent damage can result.
!
Do not operate the PLDxK-CH driver
outside of the Safe Operating Area curve.
Operating the PLDxK-CH Driver outside of
the SOA voids the warranty.
Refer to the Wavelength Electronics website for the most
up-to-date SOA calculator for our products. The online tool
is fast and easy to use, and also takes into consideration
operating temperature.
www.teamwavelength.com/support/design-tools/soa-ld-calculator/
SOA charts are included in this datasheet for quick reference,
however we recommend you use the online tools instead.
Follow these steps to determine if the driver will be operating
within the SOA.
•
Refer to the laser diode datasheet to find the maximum
voltage (V
MAX
) and current (I
MAX
) specifications
• Calculate the voltage drop across the controller:
V
DROP
= V
S
- V
MAX
(V
S
is the power supply voltage)
• Mark V
DROP
on the X-axis, and extend a line upward
•
Mark I
MAX
on the Y-axis, and extend a line to the right
until it intersects the V
DROP
line
•
On the X-axis, mark value of V
S
• Extend a diagonal line from V
S
to the intersection of the
V
DROP
and I
MAX
lines; this is the Load Line
•
If the Load Line crosses the Safe Operating Area line at
any point, the configuration is not safe
If the SOA Calculator indicates the PLDxK-CH will be
outside of the Safe Operating Area, the system must be
changed so that less power is dissipated within the driver.
See Wavelength Electronics Application Note
The Principle of the Safe Operating Area
shifting the Load Line.
After changing any of the operating parameters, recalculate
the SOA to make sure the driver will operate safely. If you
have questions, or run into difficulties calculating the SOA,
contact Wavelength Electronics for assistance.
Voltage Drop (V)
Current (A)
0.0
2.5
5.0
7.5
10.0 12.5 15.0 17.5 20.0 22.5 25.0 27.5 30.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
Figure 27. SOA for PLD5K-CH
Voltage Drop (V)
Current (A)
0.0
2.5
5.0
7.5
10.0 12.5 15.0 17.5 20.0 22.5 25.0 27.5 30.0
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
Figure 28. SOA for PLD10K-CH
Voltage Drop (V)
Current (A)
0.0
2.5
5.0
7.5
10.0 12.5 15.0 17.5 20.0 22.5 25.0 27.5 30.0
0.00
1.25
2.50
3.75
5.00
6.25
7.50
8.75
10.00
11.25
12.50
Figure 29. SOA for PLD12.5K-CH
