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Extra eyes on ESP32 Reflections ThingTwo main board?

frankcohen

Hi 14-ers, I'm seeking your help to review the third revision to the Reflections open-source hardware main board, codenamed ThingTwo. It's an ESP32-S3 in a 34 mm round double-sided board. This is my first-time to produce a hardware/software project. I'm excited and nervous. I would be glad for your eyes on the design: Identify mistakes, limitations, and poor design choices. And, make changes to improve it.

Schematic, layout, and BOM are at:

oshwlab.com/.../Reflections-Mainboard

The main repository is at github.com/.../ReflectionsOS.

I produced this to make mobile storytelling experiences. I am distributing the design under a free open-source GPL v3 software license.

Thanks for considering my ask.

-Frank

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  • in reply to fmilburn

    Thanks, here are the problems we had with the rev 2 Hoober board, and the requirements for ThingTwo. These are from https://github.com/frankcohen/ReflectionsOS/blob/main/Devices/ThingTwo/ThingTwo_project_notes.md

    What went wrong in Hoober:

    • TFT display module pads used wrong pitch, the amazing Ryan Orosz of Surface Mount Solutions in Santa Clara, California created a patch cable.

    • Power-up did not work as expected, and was unneeded.

    • GPS did not work, no satellites captured.

    • NAND pads reversed.

    • Feedback from the Element14 community says we should have no components, traces, and vias under and around the ESP32 antenna array, https://bit.ly/3Od68kH

    • Power to the display cable did not work.

    • Using Adafruit Feather ESP32-S3-Mini board definition. This appears incompatible with Platform.IO and the JTAG debugger support.

    • ESP32-S3 does not reset after upload from Arduino IDE and esptool.py v3.3.1. This is a bug in the ESP32-S3 firmware. espressif/arduino-esp32#6762

    • Adafruit_DRV2605 software library does not support custom SPI pins for the Haptic feedback motor.

    • Forgot to order PCB SMT stencils from PCBway. Had new ones produced in California by Surface Mount Solutions.

    • Original PCBway order forgot to panelize the boards. Surface Mount Solutions of Santa Clara, California did the board assembly. They really like v-score instead of drilled tabs. And "north south east and west" orientation.

    • Last minute parts swaps due to out-of-stock sitatuions.

    • Pandemic forced Shanghai city quarantine, slowing parts availability.

    THINGTWO REQUIREMENTS

    ThingTwo is the 3rd revision of the Reflections main board. It is the successor to Hoober and Sox.

    ThingTwo board changes:

    • Pickup Hoober rework changes, details in https://bit.ly/3PmWc9c

    • Remove power-on/off circuit and power button.

    • Replace GPS circuit with ATGM336H module.

    • Add power-on LED.

    • Display connector pads have corrected pitch.

    • Remove traces and vias around ESP32 antenna, https://bit.ly/3Od68kH

    • Add more room around the daughter board cable pads for easier soldering.