I want to use ESP32 with the STWD100NYWY3F external watchdog timer. Below is my connection diagram.

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On WDI with 33 pin, periodic pulses are sent to the watchdog timer. If the timer is not reset, then a low level is sent from WDO to the EN output, which should reset ESP32. EN output is constantly raised to a high level, which should block its operation, as soon as a low level is applied to 32 outputs - the timer starts and controls the system.


  1. I correctly understood the principle of operation and the scheme?
  2. Will it work with ESP32 or do I need to change something?
  3. On one of the forums I saw the following:

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Is this a problem for ESP?

  • 1
    \$\begingroup\$ The points raised in the forums are valid. What are the reasons why you don't want to use ESP's internal WDT? \$\endgroup\$ – anrieff Jun 10 at 7:53
  • \$\begingroup\$ ESP32 will be in the zone of interference, as far as I know, it may happen that the internal WDT will not be able to restart ESP. \$\endgroup\$ – Алекс Гарисон Jun 10 at 8:06
  • 1
    \$\begingroup\$ I'm using an ESP32 in a very demanding application, no issues with the WDT though. Keep in mind that even with the internal WDT (where you'd have it handled by the OS properly during updates/program upload) you'd still need to use a pretty large timeout, e.g. 10 seconds or more. \$\endgroup\$ – anrieff Jun 10 at 10:40
  • \$\begingroup\$ @anrieff Thank you!!! \$\endgroup\$ – Алекс Гарисон Jun 12 at 9:19

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