Apologies up front, this is a bit of a longer post. I started a build several months ago I wired a Pico Crumble with a RGB Cree XP-E2 CopperNova, 20mm speaker, momentary switch, 18650 3.7V battery. The LED was resistored with Red – 1.2ohm 3W, Blue 0.5ohm 1Attachment 17481W. When I wired everything outside of the hilt and pressed the momentary switch, I would get a single quiet squelch and rhythmic ticking from the speaker every 1/2 second. Neither the accent LED in the switch nor the main LED would light up despite me testing the wiring for each LED die individually (and all of the dies on the Tri Cree all at once).

I’ve removed the switch from the wiring as well and get the same result when I touch the two wires together briefly – the single quiet squelch and rhythmic ticking.

I don’t have access to an automated power supply, so all power I’ve been supplying to the board has been through the battery. I’ve tested the battery independently with a multimeter and it’s always exceeded the 3.7V (~4-4.5ish).

When I emailed Plecter it was suggested that it was a bad amp, so I sent the chip off for testing and on the testing rig the chip was able to light LEDs and make appropriate sounds. So it seems the chip isn’t the problem.

My math for the LED resistors is as follows.

Red Cree Part# XPEBRD-L1-0000-00901
80.6 Minimum Luminous Flux @ 350mA
Forward Voltage @1000mA = 2.65v
R = 3.7 – 2.65 = 1.05V / 1A = 1.05Ω
P (Watts) = R * I^2 = 1.05 * 1 = 1.05 Watts
1.05Ω, 1.05 Watts so I used 1.2Ω 3W

Royal Blue Cree Part# XPEBRY-L1-0000-00S01
650mW Minimum Radiant Flux @ 350mA
Forward Voltage @1000mA = 3.4v
R = 3.7 – 3.4 = 0.3V / 1A = 0.3Ω
P (Watts) = R * I^2 = 0.3 /1A = 0.3 Watts
0.3Ω, 0.3 Watts so I used 0.5Ω, 1W


I’ve wired and rewired it multiple times, but I get the same result. Anyone have any ideas if there’s something I’m missing?

I appreciate any help. Wiring schematic is attached.

saber wiring.jpg