ESP32 Forum

1. When i tried with Wifiscan example with Arduino-esp32 code library, i feel board is keep on resetting.
I have checked with USB cable, it was working fine.
Output screen was attached below.
Can anyone help me out, what might be the problem with dev board.

This is most likely a power supply issue. My guess is that you're running this from USB? Can you try another USB power source and/or a different USB cable?

yes, I am using USB. I have tried with different USB cables, no change.
I have also tried with Strapping pins setup given in datasheet, still no change.

Please help.

The strapping isn't the issue here. The brownout detector specifically triggers if the ESP32 sees a too low voltage on its power supply lines. Can you measure what the actual voltage of the 5V and 3.3V power supply lines on the board is?

In 5V point = 3.45V
In 3.3V point = 3.27V

3.45V? That is very, very low, and usually indicative of a power supply issue (as in: USB connector, USB cable, laptop/power brick/powerbank). You'd expect 4.5V at the very least there, and even that can lead to trouble.

Thank you ESP_Sprite for suggestions. I have given external 5V supply to the Module, working perfectly alright.

I have exactly the same problem on my two new hornbills. When powered from USB, the 5v line measures about 3.5v and triggers the brownout detector. I've tried with many different cables and USB chargers (some rated as high as 3.2A) but nothing makes a difference.I've contacted the manufacturer to see what they say, but it's a bit crap if they need external power to reach a steady 5v.

I use an Elko 220uF/16V between 3.3V and GND to supress the peek when wifi is powering up.


linuxpaul

I just want to second what /u/linuxpaul said, I have now strapped a 220uF cap across 3.3v and Gnd and it works fine. no more brownouts.