Hexagon HQ10D Driver Board
My take on the Moonlight Special
17.6mm driver board for 10x AMC7135, Dual-Channel and Off-Time-Capacitor
Nanjg105 replacement with the benefit of additional features:
- Space for 10x AMC7135 to achieve up to 3.8A without having to stack
- Dual-channel connection of the AMC7135 allowing the advantages of a dual-channel firmware
- The AMC7135 #1 (Q1) has a large solder pad under the GND connector for better heat-sinking to further minimize the risk of a flickering Moon mode
- Dedicated place for an off-time-capacitor
The circuit follows the Nanjg drivers, so the resistors for low voltage protection and C1 are behind the diode. A Nanjg can be used for harvesting parts, although R1 and R2 in my board have a 0603 footprint, but the stock Nanjg105 resistors (0805) do fit if soldered carefully.
Q1 is connected with pin5 and Q2-10 are connected to pin6. By driving one 7135 seperately you can get lower Moon, can use different kind of PWM (fast/phase) or different frequencies for the modes and have no PWM when switching the channel completely ON to get a current regulated Medium mode. That way you can get a single-LED/single-cell driver board with output >3A, good regulation, no whining and a low and reliable Moon mode.
You need to use an advanced firmware with dual-channel like JonnyC’s STAR Firmware or Toykeeper’s Moonlight Special to switch Pin5. For more firmware options you might take a look at the Firmware Repository thread to find the latest firmwares.
To reach 3.5A or even 3.8A in a single-cell/single-emitter setup you need a high drain cell and the least possible resistance in your current path (e.g. copper braided springs, thick wires).
You can use either 350mA or 380mA current regulators, but I recommend 350mA at least for Q1, as they seem to be more reliable in low PWM modes. The 7135s, that you can buy or harvest, can behave quite differently at low PWM levels like 1/255 or 2/255, depending on mA-version, manufacturer, or simply the production batch. I only get consistent results for a chosen combination of frequency/PWM-level when I use regulators as identical as possible. I already stock a certain batch seperately only to use them as Q1.
350mA as medium mode has really grown on me and with the 10D I like a mode spacing of Moon-35mA-350mA-3500mA.
The boards are slighly oversized to 17.6mm. Oshpark tends to produce a smaller copper layer than is set in Eagle and I prefer to have true 17mm of copper
Strictly speaking this board is untested. But I use these kind of boards for more than a year now and this is the 6th version, always tweaked a bit. I just ordered this newest version and post pics as soon as these are built.
In the meantime a picture from an earlier version successfully installed in the Convoy M1.