I am in need of a PCB design review in order to find an issue with my design - Page 1
Forum section: electronics / general

author: Hague Tech
author_rank: Contributor
timestamp: June 09, 2025, 03:23:03 pm
content: I have designed a PCB for a small battery powered hand-held gaming device that utilises the ESP32-S3. I used the ESP32-S3 Zero dev board as a reference and closely followed the recommended layout from the chip’s datasheet. The PCB was manufactured by JLCPCB however it is not able to connect to a PC, and I do not know why and lack the experience to troubleshoot.Does anyone know of any PCB review services that would be able to help?I have included the schematic and PCB layout/gerbers in if anyone fancies having a quick look to see if it is something obvious and easy to fix but that is wishful thinking. I appreciate any help.

author: tooki
author_rank: Super Contributor
timestamp: June 09, 2025, 03:28:53 pm
content: Please share the PCB layout as images or PDFs, so that we can view them in the browser. (I normally browse on my iPad; I don’t have a Gerber viewer on it.)

author: Hague Tech
author_rank: Contributor
timestamp: June 09, 2025, 03:40:27 pm
content: Quote from: tooki on June 09, 2025, 03:28:53 pmI have included a png image of the PCB layout, thanks for the suggestion.

author: Pseudobyte
author_rank: Frequent Contributor
timestamp: June 09, 2025, 08:12:28 pm
content: Break out the multimeter and start with the basics.Check the power rails (ie, do i have 5V where i expect it, do i have 3V3 where i expect it, etc..)Check the reset pin of the ESPCheck the boot pins/button actions

author: WattsThat
author_rank: Frequent Contributor
timestamp: June 09, 2025, 10:44:49 pm
content: Uh, first mistake. Assuming it’s a layout problem. Consider:Bad soldering?Component inserted incorrectly?Incorrect component?First up is a thorough visual inspection. That covers the above.Then get out the DMM and start confirming interconnections…

author: thm_w
author_rank: Super Contributor
timestamp: June 10, 2025, 12:10:36 am
content: CC1/CC2 resistor should be 5k1 not 1k5.Is a battery installed? The output from the regulator might not work without a battery.

author: Hague Tech
author_rank: Contributor
timestamp: June 10, 2025, 09:11:17 am
content: Quote from: thm_w on June 10, 2025, 12:10:36 amSame issue with battery connected. The 1.5k thing was a typo I must have missed all the way through somehow but that is something that will certainly effect USB connection, I will try and change those resistors. Good spot on that, thanks for the help!

author: thm_w
author_rank: Super Contributor
timestamp: June 10, 2025, 08:08:37 pm
content: So with or without battery connected MCU still receiving 3.3V ok? Follow what Pseudobyte posted above.https://docs.espressif.com/projects/esp-idf/en/v5.4.1/esp32s3/api-guides/dfu.htmlhttps://docs.espressif.com/projects/esptool/en/latest/esp32s3/advanced-topics/boot-mode-selection.html#select-bootloader-mode

author: Hague Tech
author_rank: Contributor
timestamp: June 11, 2025, 02:51:43 pm
content: Quote from: thm_w on June 10, 2025, 08:08:37 pmSo I broke out the old multimeter as per Pseudobyte's advice and found that there are 3.3v going into the MCU and out of the LDO etc and 5v coming from the USB Vbus, which is good. However, while I was probing I descovered I clearly do not understand how push buttons work, they are all wired up inverted meaning they constantly output a signal when not pressed and output 0v when pressed. This descovery did allow me to operate the boot and reset buttons by releasing them intead of holding them and managed to get my PC to discover the MCU. But, the PC does not recognise the MCU as a valid device and says "unknown usb device descriptor request failed".I still have not chaged the incorrect 1.5kohm resistors for 5.1kohm ones but will do that tomorrow and see if that helps.Thanks again for all the help so far.

author: Hague Tech
author_rank: Contributor
timestamp: June 12, 2025, 01:03:23 pm
content: Situation update, I replaced the 1.5kohm resistors for 5.1kohm resistors but the same issue persists. Now I have corrected the resistors and can put the MCU in boot mode properly and have the confidence that the voltages are correct I do not know what to try further to slve this issue. I have Google searched extensively but I cannot find anyone who had this issue using the ESP32-S3's native USB connection.

author: thm_w
author_rank: Super Contributor
timestamp: June 12, 2025, 09:04:25 pm
content: If you have the ability to read the serial output of the ESP32 as per link above that might tell you something."After reset, the second line printed by the ESP32-S3 ROM (at 115200bps) is a reset & boot mode message"Also can try a software tool likeUSBDeviewto see if the device is listed at all.

author: Hague Tech
author_rank: Contributor
timestamp: June 13, 2025, 01:41:07 pm
content: Quote from: thm_w on June 12, 2025, 09:04:25 pmThe device is listed in the nirsoft tool but it just populates as unknown and all the serial numbers and IDs etc are 0000... It doesnt show up on any COM ports so I am having trouble connecting it to any sort of serial monitor as there is no COM port to select to get it connected in any of the IDEs/IDFs. The only help I can find from Espressif is connecting using a UART bridge but I am using the chips native USB. I did try installing a UART bridge virtual com port put that didnt work.

author: thm_w
author_rank: Super Contributor
timestamp: June 13, 2025, 08:40:15 pm
content: The serial output would be the U0Tx and U0Rx pins on the ESP32 afaik. You'd need a 3.3V serial adapter or logic analyzer, etc. to read these.