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indigo 2025-09-22 21:04:51 -05:00
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@ -62,7 +62,7 @@ To prevent pixels from being re-rendered, I stored information in the green chan
I wrote a GDB script to benchmark performance with and without border tracing. Results improved up to 75%. I was planning on including a table and images here, but I'm running out of time writing this article. I will likely add it later!
## Hardware Design
Hardware was relatively straight forward. I miscalculated how much power was consumed by a power of 10- so my first PCB used non-rechargeable zinc-ion batteries, as this was the cheapest solution I could find. My first card worked without issues, as the only real circuitry was debouncing and a step-down switching regulator.
Hardware was relatively straight forward. Every iteration fit on a 2 layer PCB. I miscalculated how much power was consumed by a power of 10- so my first PCB used non-rechargeable zinc-ion batteries, as this was the cheapest solution I could find. My first card worked without issues, as the only real circuitry was debouncing and a step-down switching regulator.
After discovering my error, I decided to make a more complex design that allowed recharging via USB-C for AAA batteries. To maximize battery longevity, a switching regulator was used for the step-up (battery) supply, while a simple linear regulator for USB-C. To avoid the batteries from discharging, I put a voltage supervisor to shut down the switching regulator at 1V. The switching regulator has true shutdown- blocking inputs when shut off. The voltage monitor uses a capacitor to time how long it should wait until turning back on above 1V. While finishing up the PCB I was tired and didn’t care to calculate this value, so I just slapped a 1uF cap down- hence the card takes around 5 seconds to become powered after a battery is inserted. Two ideal diode ICs are used for supply ORing so the supplies aren't in conflict while charging.