MELDv3 in Fenix HL50 & Sunwayman C10R

MELDv3 boards came in! This version brings big improvements to the SEPIC converter on the white channel, mostly in the area of thermal performance. It also makes an electrical change that allows the SEPIC to run well at much lower battery levels if the light is running on primary cells.

  The inductors are much bigger to better handle high current, so to avoid increasing the stack height I rearranged the daughter board so that they are both on the top side.

I did two projects right away with the new boards, one of which is to upgrade my new Fenix HL50 headlamp. I was very excited when this headlamp was released because single-CR123 headlamps are rare and I don't like any other battery setups, but of course the UI is terrible and needed an upgrade.

As soon as I got it, I opened it up to see how much room there was. The construction is pretty good. Here you can see the stock driver with a daughter board that sits vertically:

I was able to fit MELDv3 by removing the inductors and free wiring them up in the vertical space.

My standard MELD LED board with XB-H and XQ parts fit with one edge filed down. I also had to drill out the reflector slightly to get it around the LEDs. Here's the LED board installed and wired up:

And the finished result, the perfect headlamp:

And here's the second project with MELDv3, a Sunwayman C10R. I really like the construction on the C10R. It has a nice big reflector so I was able to fit an XP-size LED board in it with an XP-L as the white emitter. MELDv3 went in pretty easily by epoxying a momentary switch onto the main board:

Here it is with wires attached, going into the head of the light. Not shown here is a grounding ring needed to make contact with the body (this difficult grounding is my only complaint about the design of the C10R). Also shown is the MELD XP LED board with all LEDs installed and notches cut to fit the wires:

And all wired up: