A few weeks ago I was on a junkyard that had a decent amount of telecommunications equipment. Mainly racks of old cellphone 3G (I think) basestations from which I got a load of some interesting RF stuff. I also found a pretty rough looking switchmode power supply from the ground, made by Ascom energy systems. It had been sitting out in the rain for quite some time (I think at […]

Here’s a quick project I made in couple days or so. It is a push-pull step-down laser diode driver based on LT1683 SMPS controller chip from Linear Technology. The circuit works with 12-18V input and can put out about 1A to a 2V load. I used a PL140-105L planar ferrite transformer from Coilcraft which is quite overkill for this application (it is rated for 140W). The circuit has a current clamping circuit (so […]