Meanwhile I have done a small redesign of the PCB. The changes to v2.1 are:
- Two additional resistors have been added to the gates of Q1/Q2 to form a voltage divider
In v2.0, Vsg of Q1/Q2 was close to the max rating when using 6 LEDs. The additional resistors allow the use of up to 8 LEDs. In the course of adding these parts, all resistors have been renamed / renumbered.
- The width of the track at the anode of T1 has been increased
In v2.0 it burned when T1 fired repeatedly
- Capacitor C12 (gate of T1) has been removed
The part was not necessary and has been removed
- Adjustable resistor R15 has been moved
R15 (previously R13) has been moved slightly so it doesn't touch neighboring components
- A couple of cosmetic changes
In spite of the changes, the dimensions of the PCB remain the same. One part was removed and two parts were added to the BOM.
The link to the design source files (first post) now links this new design. You will need this, it contains the BOM and the asy guide.
Be aware of a slight change of plan:
Initially I planned to have the plating-through process done though the boards are single-sided only. It was meant to better hold the components on the PCB and to avoid that traces get torn off. With my current supplier, this process would nearly double the cost of the boards, same cost as dual-layer. Since the boards I have so far populated show very good mechanical strength with kinked component legs, I decided I could get away without the plating through.
The copper traces of the PCB are 100% HAL solder-coated and the kinked ends of the component legs solder to the traces along their full length, this is what makes it strong.
This morning I have ordered 5 sqdm of the new boards. The resulting number of boards will probably cover the qty so far requested. It will take 1 to 2 weeks for them to arrive here. I'll build one to be sure that the redesigned PCB is OK, the rest will be sent out until my stock is depleted.
Should until then more requests pile up, there'll be another round.
Eventually I will need everyone's mailing address. You can send it by e-mail or PM (don't put it on the forum).