USB Not Recognized

[uranyumx]

Hello,

On my custom designed PCB, there is a USB port for battery charging and programming ESP32 microcontroller. When I plug in to the PC, I get "USB Not recognized" message. In addition, the two LEDs are light up. In the datasheet of the charger IC (STBC08), it says there is "not enough power". But I checked the power pin (1st pin) of the USB port, there is 5.1V. So why is there a problem? Do you have a solution for that?

I attached the schematic of the power management part.

Thank you,

 

[KlausST]

Hi,

The PC message: "USB Not recognized"
means the USB_host inside the PC can not communicate with the USB device.

From your schematic there is nothing that can communicate vis USB.

So, I´m not surprised about the message.

***
Regarding your LEDs.
What do you expect?

****

Btw: Your schematic shows "3.3V linear voltage regulator"
It does not seem to be "linear"

Klaus

 

[uranyumx]

I have USB-UART bridge as well for programming the microcontroller.
I expect "Power ON" LED is ON only.

 

[KlausST]

Hi,

CP2102:
* missing power supply capacitors
* missing GND connection

Klaus

 

[uranyumx]

Thank you @KlausST ! I fixed the GND connection with a jumper wire. Are the power supply capacitors critical?

Why are the both two LEDs keeping the lights ON?

 

[KlausST]

Hi,

Are the power supply capacitors critical?

I personally think the manufacturer knows best. If they recommend the capacitors, I´d use them.
If you don´t use them, don´t complain when it (temporarily / randomly) fails.

*****

Why are the both two LEDs keeping the lights ON?

Again: What do you expect? .. and why?

I see nothing wrong ...

Klaus

 

[uranyumx]

I personally think the manufacturer knows best. If they recommend the capacitors, I´d use them.
If you don´t use them, don´t complain when it (temporarily / randomly) fails.

I see, let me check it.

Again: What do you expect? .. and why?

I see nothing wrong ...

All right, let me try to flash the firmware of the microcontroller.

 

[andre_luis]

Did you see what appears on Device Manager panel on the devices tree ( assuming you are on Windows ) ?
If so, did you check if at least what error was diagnosed and/or if some device ID was caught ?
If so, did you search for its device driver somewhere ?

 

[FvM]

I'm missing info about voltage at +Bat and 3.3V node.

 

[uranyumx]

Did you see what appears on Device Manager panel on the devices tree ( assuming you are on Windows ) ?
If so, did you check if at least what error was diagnosed and/or if some device ID was caught ?
If so, did you search for its device driver somewhere ?

After fixing the GND connection, I saw the USB-UART bridge IC name. Then I successfully downloaded it. Now I will try to upload the firmware.

--- Updated Apr 12, 2024 ---

I'm missing info about voltage at +Bat and 3.3V node.

The battery voltage is 3.7V (represents with Bat+)