ESP32 Forum

Posted: **Sat Nov 15, 2025 9:26 pm**

Hi, I'm having trouble powering my ESP32 S3 CAM ESP32-S3 by applying 5V to the 5V pin. The ESP doesn't respond, the "ON" LED doesn't light up, and there's no voltage on the 3.3V pin. However, when I connect the ESP to my computer via USB cable, everything works fine. The problem is the power supply from a 2s LiPo battery -> 5V regulator -> ESP. The voltages are definitely 5V, as I measured them with a multimeter. Thanks for any help.

Posted: **Sun Nov 16, 2025 5:45 pm**

Hello, can you post a picture/ ckt diagram of your connection?

Posted: **Mon Nov 17, 2025 2:03 pm**

Hello, can you post a picture/ ckt diagram of your connection?

The ESP is connected to an MPU9250 accelerometer, a barometer, and five servos. The servos are powered by 6V. The power supply is a simple 2s lipo connected to a 5V regulator or step-down switch for these servos.

Posted: **Mon Nov 17, 2025 5:53 pm**

If it works when connected po a pc but not when is direct powered by 5V, then the cause might be the 2 transistors used to generate reset and boot signals by the usb to serial converter. Not sure if your board has them but it worth to check the state of reset pin. if low when powered by 5V, but high when connected to PC then most likely you have the 2 transistors, and they are not working properly.
Give us the exact name of your s3 cam board or identifier.

Posted: **Tue Nov 18, 2025 4:20 pm**

If it works when connected po a pc but not when is direct powered by 5V, then the cause might be the 2 transistors used to generate reset and boot signals by the usb to serial converter. Not sure if your board has them but it worth to check the state of reset pin. if low when powered by 5V, but high when connected to PC then most likely you have the 2 transistors, and they are not working properly.
Give us the exact name of your s3 cam board or identifier.

When I connect it to PC, the reset pin is high, but when its connected to 5V, reset pin is low.
My board: ESP32-S3-WROOM

Posted: **Wed Nov 19, 2025 8:20 am**

Not sure which dev kit type ESP32-S3-WROOM is.
It might be the one from Waveshare (https://www.waveshare.com/wiki/ESP32-S3-DEV-KIT-N8R8) which has a single USB type C connector and a USB hub in between. The hub has 2 downstream ports connected to ESP32-S3 USB port and to USB2serial chip
If this is the case then when connected to PC it should enumerate 2 COM ports.
For such a topology if upstream port is not connected the downstream ports are inactive. Not sure what means inactive wrt downstream DP/DM signals, but usb2serial chip might understand this state in a way that will generate a reset to esp32.
I’m just speculating. First, I don’t know if this is the case and which chips are used for usb2serial and hub, second my knowledge on usb hubs is limited.
So need a better identifier for your board to see if my assumption is right, and if this is the case, someone with a better knowledge on usb hubs to comment if the board can be used wo usb connection.

Posted: **Wed Nov 19, 2025 2:29 pm**

Not sure which dev kit type ESP32-S3-WROOM is.
It might be the one from Waveshare (https://www.waveshare.com/wiki/ESP32-S3-DEV-KIT-N8R8) which has a single USB type C connector and a USB hub in between. The hub has 2 downstream ports connected to ESP32-S3 USB port and to USB2serial chip
If this is the case then when connected to PC it should enumerate 2 COM ports.
For such a topology if upstream port is not connected the downstream ports are inactive. Not sure what means inactive wrt downstream DP/DM signals, but usb2serial chip might understand this state in a way that will generate a reset to esp32.
I’m just speculating. First, I don’t know if this is the case and which chips are used for usb2serial and hub, second my knowledge on usb hubs is limited.
So need a better identifier for your board to see if my assumption is right, and if this is the case, someone with a better knowledge on usb hubs to comment if the board can be used wo usb connection.

I have an identical board as in the link: https://pl.aliexpress.com/item/10050073 ... edium=shop ping&utm_campaign=PA_Bing_PL_PMAX_ALL_MaxValue_20250221_newstore&utm_content=ALL&utm_term=P%C5%82ytka%20rozwojowa%20ESP32%20S3%20CAM%20ESP32-S3%20N16R 8%20dual%20TYPE-C%20OV2640%2FOV5640%20Camera%20WiFi%20Bluetooth%20modu%C5%82%20built-in&msclkid=92e1e96132f3132107d2807ce124aae6&gatewayAdapt=glo2pol

Posted: **Wed Nov 19, 2025 2:29 pm**

Not sure which dev kit type ESP32-S3-WROOM is.
It might be the one from Waveshare (https://www.waveshare.com/wiki/ESP32-S3-DEV-KIT-N8R8) which has a single USB type C connector and a USB hub in between. The hub has 2 downstream ports connected to ESP32-S3 USB port and to USB2serial chip
If this is the case then when connected to PC it should enumerate 2 COM ports.
For such a topology if upstream port is not connected the downstream ports are inactive. Not sure what means inactive wrt downstream DP/DM signals, but usb2serial chip might understand this state in a way that will generate a reset to esp32.
I’m just speculating. First, I don’t know if this is the case and which chips are used for usb2serial and hub, second my knowledge on usb hubs is limited.
So need a better identifier for your board to see if my assumption is right, and if this is the case, someone with a better knowledge on usb hubs to comment if the board can be used wo usb connection.

I have an identical board as in the link: https://pl.aliexpress.com/item/10050073 ... pt=glo2pol

Posted: **Wed Nov 19, 2025 7:10 pm**

Obviously, my assumptions are wrong

It looks to be a normal dev kit with 2 usb connectors and no usb hub.
I could not find the schematic for this specific board but looking at the pictures I would expect it follows standard ESP32-S3-DevKitC-1 (https://docs.espressif.com/projects/esp ... index.html) at least when it comes to usb2serial.
Pls provide the part no of usb2serial convertor chip on the back of the module

Posted: **Fri Nov 28, 2025 4:21 pm**

Obviously, my assumptions are wrong
It looks to be a normal dev kit with 2 usb connectors and no usb hub.
I could not find the schematic for this specific board but looking at the pictures I would expect it follows standard ESP32-S3-DevKitC-1 (https://docs.espressif.com/projects/esp ... index.html) at least when it comes to usb2serial.
Pls provide the part no of usb2serial convertor chip on the back of the module

convertor : CH343P

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ESP32S3 does not work when powered on 5V pin

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Re: ESP32S3 does not work when powered on 5V pin