Firefly PCBs powered by the CH32V003.
These boards periodically flashes a xenon flash based on a timer, which gets accelerated when it detects flashes from surrounding PCBs.
There are currently 2 flash-detection circuits undergoing testing:
-
A reverse-biased diode using the ch32v003's internal OPA & ADC for samplingling
-
A I2C ambiant light sensor for more "advanced" applications
The flash trigger isolates the hi-voltage trigger and the low-voltage circuitarry with a triac circuit, and uses a mosfet to trigger the flash.
- Dual light-sensor: one via i2c, one via photodiode
- USB via ch32usb
- 7 seg for number display
- Flash activation circuit (high voltage)
- Programming ports
Check firmware folder
Here's an example output for detection light intensity with the photodiode:
It's reverse-biased btw
Check diagram:
| Item | Price | Where |
|---|---|---|
| PCB | 4$ | elecrow |
| Stencil | 2$ | elecrow |
| Components (check hardware bom) | $30 | lcsc |
| Shipping | varies by region | none |
