QuinLED ESP32 Revision History

To try and keep track of past revisions and the major changes between the versions here is a list of past releases and some of the things that have changed.

QuinLED-ESP32
- Version 1
  - Revision 2
    - 2021-03
      - Initial release version
  - Revision 3
    - 2021-07
      - Changed EN capacitor to higher value for better chance of auto flash mode succes
- Version 2
  - Revision 1
    - 2023-03
      - Redesign to address an issue with a voltage regulator that would sometimes die after a few hours of operation since a certain batch of chips
        
        Fully re-designed voltage regulator stage with a beefed up LDO
        
        Much larger package for improved heat dissipation
        
        Keeps 750mA onboard PTC and reverse feed diode protection
        
        Extra stabilization of power stage to prevent brownout situations often seen on generic ESP32 dev boards
      - Changed USB-to-Serial converter to newer and smaller type
        
        Still CH340 based
      - Changed chip used for auto flash mode support
      - Raised value of EN capacitor even more to slow down for better succes rate on slower PCs
      - Added Blue LED on GPIO2
  - Revision 2
    - 2023-07
      - Changed board from 2 layer to 4 layer
        
        To help with potential EMI issues for certification
- Version 4
  - Revision 1
    - 2026-10-31
      - Full redesign!
      - Switched to ESP32-PICO-MINI-02-N8R2 modules
        
        Comes with 8MB flash and 2MB PSRAM
      - Switched to custom GPIO layout and pinout
      - Onboard LDO(s) and 3V3 direct in
        
        Using a QuinLED Dig-Uno v4 / Dig-Quad v4 the board switches to direct 3V3 in mode
        
        Still compatible with 5V USB-C and 5VPIN
      - No diode power management
        
        Fully done with reverse blocking and current limiting load switches
      - Extra protection
        
        Extra ESD protection diodes on 3.3V and 5V
        
        “Overvoltage protection”
      - 2x Green LED for 5V power in
        
        1x Orange LED for 3.3V power
        
        1x Blue LED for GPIO32
      - Ethernet version redesigned to a single PCB
      - Upgraded power management and tracks
      - Return of the reset button
        
        Now has a reset & boot button
      - Always onboard I2S PDM microphone
        
        High quality digital microphone on all boards