Laser Drivers

Some of my laser drivers for laser diodes

LaserDriver - A6211

Recently, a friend of mine talked to me about his new hobby - handheld lasers. A big downside of the cheap lasers purchased from China turns out to be the design of their laser diode driver boards. Most of them are based on the LM358 operational amplifier and use a bipolar transistor to regulate the current. There is one major problem with this configuration - the transistor dissipates a lot of heat - especially if the voltage of the batteries is significantly larger than the forward voltage of the laser diode.