ESD Protection

[smeisner]

Nice work so far!!

Looking at the design, I was curious about static discharge protection. Is that what R8 & R9 are for? I don't have the latest version of Kicad, so I couldn't open the schematics, but looking at the BOM, it looks like these resistors may be for ESD.

[diminDDL]

From, Hardware design with RP2040:

these I/Os do require 27Ω series termination resistors (R3 and R4 in Figure 9), placed close to the chip, in order to meet the USB impedance specification.

Regarding ESD, the RP2040 meets all the standard ESD specifications of 1-2kV Human Body Model, additional USB ESD protection may be added later depending on the available board space and cost.

[smeisner]

Thanks for the reply! I am working on a ESP32-based thermostat (https://github.com/smeisner/smart-thermostat) and was concerned about ESD. This is why I was asking. I am doing a final rev of the PCB and was hoping to incorporate protection into it.