LDM9T
Chapter 5: Operation
Rev G, Jan 22, 2017
Page 11
5.5. Safe Operating Area (SOA)
The safe operating area for the mount is basically the area at which the thermal
power of the laser diode can be removed and dissipated by the LDM9T. How
much power the mount can dissipate depends on a number of factors, ambient
temperature and set point temperature being the most important. The graph
below can be used to determine how much power the mount can efficiently
remove and maintained proper stabilization. Most low and medium power laser
diodes will fall within this curve.
To calculate the thermal power of the installed laser diode two factors need to be
known, forward operating voltage (V
F
) and the operating current (I
op
). Both are
typically published in all laser diode spec sheets.
𝑃
𝑡ℎ𝑒𝑟𝑚𝑎𝑙
= (𝑉
𝐹
)(𝐼
𝑜𝑝
)
Blue and violet laser diodes tend to have much higher forward voltage drops
meaning they produce more thermal power that needs to be dissipated than a
standard laser diode.
Figure 6 Power Dissipation vs. Ambient Temperature
