What is Laser Diode Driver?
In the most ideal form, it is a constant current source — linear, noiseless, and accurate — that delivers exactly the current to the laser diode that it needs to operate for a particular application.
The user chooses whether to keep laser diode or photodiode current constant and at what level. Then the control system drives current to the laser diode safely and at the appropriate level.
The block diagram in Figure 1 shows a very basic laser diode driver (or sometimes known as a laser diode power supply). Each symbol is defi ned in Table 1. Laser diode drivers vary widely in feature set and performance. This block diagram is a representative sample, meant to familiarize the users with terminology and basic elements, not an exhaustive evaluation of what is available on the market.