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Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
@DrAzzy
I'm going to remake the drivers for the LEDs to use constant current drivers, AMC7140 linear adjustable current regulators. ~$1 each, but they've got builtin OE pin, current handling up to 700ma.
So, I'm gonna crank the voltage on the LEDs up so I'm running them in series instead of parallel, and have:
2x3W Cool/Warm White, 700ma (at ~4.1v forward voltage)
2x3W Very cold white (replacing the current blue) at 350-700ma, depending on power constraints and how it looks.
3x1W Yellow, 350ma. These will either be phosphor yellow, or a mix of phosphor yellow and 585nm yellow.
3x1W Red, 350ma. Will likely use different shades of red to get better color rendition. The pink LEDs look like utter shit, and I'm not making that mistake again, and I can't find any phosphor based leds that give reds (not pinks polluted with a horrifying amount of royal blue, such that uv-reactive stuff around fluoresces)
I'm also making a base plate for the Espruino to sit on that will include regulators with caps on them (like always should have been). The espruino will fit on some pin strip that connects to all pins, and routes those to connectors with power and ground, to simplify wiring (right now it's a total rats nest in there, and very difficult to work on). I've been having problems with the LCD freezing, and i think it happens because of a voltage dip/spike confusing it, as it's running off a 3.3v regulator with no cap on the output or input, along with the Wiznet and an EL inverter.
I'm hopeful that the better power distribution system will solve the problems I've had with the BMP180 - I've got my fingers crossed that the problem is a poor connection, since the connector felt loose when I was last poking at it, and the BMP180 works on the bench, just not installed.
I had the first version of it together and soldered up on sunday, but it failed the smoke test - If I ever find the person at microchip who decided to use two different pinouts on their positive regulators, I'll wire him up backwards and pass a current through him.
Edit:
New LED loadout will be:
Vled=9.4v, leaving ~9v to drive the LEDs after the dropout on the AMC7140.
3x 1W (350mA @ 3.0) Ice Blue (couldn't get 3W ones)
2x 3W (700mA @ 3.8) Cold White, nice bright LEDs.
2x 3W (700mA @ 3.4 - chinese watts) - I've been trying to source better ones without luck.
3x1W (350mA @ 2.9) yellow LEDs with phosphor (these seem very hard to get now, unfortunately)
1x5W 630nm (1A@4.5-5.5V) red + 1x 3W 660nm (350mA @ 4V - chinese watts again) red dual chip, run at 350mA in series. The 5W one is pretty excessive, but I'm hoping I'll be able to get 350mA through it with the voltage I have available. It will be tight.
This will give me about the same total power consumption at full brightness that I have now, but with almost 50% more of that power going to the LEDs - 22.3W
New driver:
