Questions tagged [usb]

USB is Universal Serial Bus. If your question relates to a specific chip, please mention it in your question.

Filter by
Sorted by
Tagged with
0 votes
0 answers
34 views

Scales NCR SelfServ Checkout what protocol is used [closed]

There is a weighing security platform from the NCR self-service checkout, there is no SDK for it (or I did not find it). I would like to understand what protocol is used to get the weight. About the ...
user avatar
0 votes
1 answer
93 views

How to make a USB hub with 48 ports or more?

I want to make a USB hub with 48 ports or more, because I have many flash drives. I need to switch different flash drives to do different things. The USB hub communicates with the computer through the ...
user avatar
0 votes
1 answer
56 views

Is it ok to short data lines of USB-C

USB type C has 2x DP+ and DP- on the connector. When laying out the PCB, is it ok to short each DP+ and DP- together?
user avatar
  • 555
0 votes
1 answer
44 views

PCB Routing Considerations for multiple USB Port Types for USB 1.1 Full Speed

I wanted to make a device that has a USB A and a USB C connector on apposing sides of the PCB, similar to the attached image. These USB connectors would be connected to the same USB port, the MCU I ...
user avatar
0 votes
0 answers
21 views

What is a common non-SMT audio codec module with USB interface? [closed]

I am looking for a relatively cheap, audio codec with USB interface. Only thing I could find was PCM- series device from Texas Instruments, but they are too tiny. Also, I have 2 more related questions:...
user avatar
5 votes
2 answers
146 views

What prevents old (low current) USB cables from catching fire if used to Quick Charge modern devices (at high-current)?

Let's say I have A very old Micro-USB cable. It's USB 2.0 and rated for a max current of 5V, 0.5A (2.5W). A modern, power-thirsty, quick-charging tablet that charges over micro-USB at a max of 100W. ...
user avatar
0 votes
1 answer
61 views

Mysterium Keyboard ATmega32a malfunctioning. "USB device not recognized."

I tried sourcing all the parts for this keyboard. I soldered everything up and when I plug in the keyboard I immediately get an error message "USB device not recognized": My first though ...
user avatar
-2 votes
0 answers
25 views

Could you recommend USB-Serial Bridge Controller IC for WebSerial? [closed]

I'm looking for new USB-Serial Bridge Controller IC. I was using CP2102, but it cannot be detected by chrome WebSerial API on Windows OS. I think CP2102 driver is too old to give a proper information ...
user avatar
0 votes
0 answers
23 views

How to connect shield of USB connector for powering purpose only?

I have a PCB design for which I want to use a portable battery pack (a.k.a. power bank) to power my circuit. I plan on using a micro USB B-type connector. I don't have any other application for this ...
user avatar
0 votes
0 answers
47 views

USB-A 12V Output?

I am very confused by PowerBanks. We bought some power banks and I can read this on the back: It seems the power bank can output 12V through the USB cable. Is that true?
user avatar
  • 345
1 vote
0 answers
50 views

How do I connect a micro USB B-type interface to a microcontroller only for the purpose of providing power?

I want to connect a micro USB B-type connector to the microcontroller, datasheet: here. From this post I got to know that if I am not using D+ and D- lines, I need to connect them to the resistors (...
user avatar
1 vote
1 answer
77 views

How does USB passthrough charging work?

I am currently making a keyboard for a phone. It connects to the phone using USB-C. I'd like to be able to charge the phone while the keyboard is connected, so I need some kind of pass-through ...
user avatar
  • 623
1 vote
1 answer
47 views

USB-C passthrough (including CC line) not making connection

I'm trying to make a USB-C switcher. I'm using a rotary switch (center) to have one input USB-C receptacle switch between two output receptacles. This is so I can plug my keyboard into the input and ...
user avatar
  • 11
0 votes
0 answers
38 views

Charging board cuts out when unplugging USB cable

I’m using a Lithium battery charge/discharge board with 5V regulator and USB-C input to power a gaming handheld. It’s important that I be able to run the handheld and charge the battery at the same ...
user avatar
0 votes
1 answer
35 views

Correct Dielectric Height on Differential Impedance Calculation?

I'm designing a custom PCB around the Raspberry Pi RP2040 MCU. Their hardware design guideline said the traces between the USB and the termination resistors should have a differential impedance of 90 ...
user avatar
  • 445
2 votes
2 answers
127 views

Problems increasing VCO frequency above datasheet recommendations

Firstly, yes I contacted ST for answers. Until now, no answer. I'm using STM32F429 MCU and embedded USB FS PHY. To keep the 48 MHz USB PHY clock the maximum PLL clock that I can achieve is 168 MHz, ...
user avatar
0 votes
1 answer
31 views

Can I power a router that requires 12V-DC via a 5,5mm input by using a powerbank that can output 12V DC over USB [closed]

I have a powerbank that can output 5V-3A/9V-2A/12V-1,5A over USB. The router I would like to power came with a 12V-1A adapter and uses less than 12W. If I were to buy a USB to 5,5mm adapter cable, ...
user avatar
1 vote
0 answers
59 views

Is it OK to use manufacturer vendor ID when using virtual COM port example?

I am using a PIC32mz microcontroller for a serial port emulator application. Example code is working fine. But if I want to sell this product, do I need to get a new vendor ID? Is it OK to use the ...
user avatar
1 vote
2 answers
125 views

How can I pass serial data through a Raspberry Pi Pico from USB to GPIO pins to be read in another Pi Pico? [closed]

I read that the Pi Pico/RP2040 has 2 UARTs. If I want to send data from a computer to a Pi Pico, how should I create a UART that uses USB? Micropython expects pin numbers to create a UART. If I use ...
user avatar
2 votes
2 answers
198 views

C-type cable trying to make an OTG cable but only 3 wires - black, red, and blue

I have a C-type cable with only three wires. I took apart the cable to get a better look inside and I only have 3 solder points. I'm trying to make an OTG host of the C cable that I have. Where do I ...
user avatar
0 votes
1 answer
58 views

What happens if the pins of two different usb thumb drives touch each other?

What happens if the pins of two different usb thumb drives touch each other? Can the data get corrupted? Can the data move from one drive to another? Can the circuits get damaged?
user avatar
-1 votes
0 answers
53 views

How do I access USB A connectors when there is not enough space of a standard USB plug?

I've just implanted a Raspberry Pi 3B+ and a radio tuner board (the white PCB below the Pi in the picture below) into a fairly cramped enclosure and now have an issue with its USB connectors: I've got ...
user avatar
  • 401
0 votes
2 answers
64 views

Are large decoupling capacitors necessary for USB hub plugs

At the bottom of this data sheet: https://datasheet.lcsc.com/lcsc/1811151645_CoreChips-SL2-1A_C192893.pdf the reference circuit diagram shows huge 100uf decoupling capacitors connected to the USB ...
user avatar
  • 55
30 votes
2 answers
5k views

Why can't USB-C receivers be as small as their USB-A counterparts?

We're all familiar with the USB-A 2.4 GHz receivers from companies like Logitech that are absurdly small and barely protrude from the port. But when looking at available USB-C equivalents, they are ...
user avatar
  • 411
1 vote
1 answer
96 views

Splitting a USB-C for aux power

I'm building a mechanical keyboard and I need more current from my PC than I can get from one usb port. Can buy/make a usb splitter that I can plug into two A ports on my PC and plug into my USB-C MCU?...
user avatar
0 votes
3 answers
74 views

Help find a usb to ac cord [closed]

I've been looking every where for a cord that is powered by usb with an ac outlet on the other side so I can plug the usb into a portable battery and have an ac outlet can someone please tell me where ...
user avatar
3 votes
1 answer
98 views

Replacing keyboard USB-A cable with a USB-C female connector

I have a keyboard with a long non-detachable USB-A cable that I would like to replace with a USB-C female connector. My end goal is being able to detach the keyboard like a portable device and use it ...
user avatar
0 votes
0 answers
29 views

3.3 V switching off 3.3 V or 5 V

I'm hacking a device that uses USB 2.0 for another purpose - the USB 2.0 was for a communications card, and I'm changing it for flash USB storage. I have the device working (it uses the USB storage) ...
user avatar
3 votes
2 answers
109 views

Connect multiple devices with USB

Consider a setup with 1 "server" device and 4 "client" devices (all are SBCs with Ubuntu installed). I would like to connect the 4 clients to the server, using USB/serial. Ethernet ...
user avatar
  • 151
1 vote
1 answer
70 views

COM Port not Detected on Windows for CP2102 on Custom PCB

I am using CP2102N-A02-GQFN24 on my custom PCB to program my ESP32 board. I am not able to see any COM port on my Windows 10 PC. I can connect to an off the shelf CP2102N-A02-GQFN28 USB UART bridge ...
user avatar
  • 21
1 vote
0 answers
60 views

Capturing High Sample Rate I2S via USB

Recently, I started working on a project to convert my Sony XDR-F1HD radio to a device that I can connect to over ideally USB to record the RF signal off of the air. All demodulation and processing is ...
user avatar
0 votes
1 answer
36 views

MaxLinear XR21B1422 OTP programming

I have a MaxLinear XR21B1422 USB-UART bridge. I want to change the configurable GPIOs. Its possible to program the internal OTP through USB commands, but I have no idea how to do it. There is no ...
user avatar
  • 11
0 votes
1 answer
42 views

USB 1 to 2 switch wiring

I have 1 USB hub with mouse and keyboard connected and I'd like to build a switch to be able to switch this hub between 2 PCs. I have a 3-position toggle switch with only 2 contact pairs, so I can ...
user avatar
  • 105
1 vote
1 answer
67 views

CH340G set of chip partially working

I bought quite a number of these CH340G USB-to-UART chips for a project. I initially mounted them on PCB and soon discovered some of them are working and others don't. To help me testing each ...
user avatar
4 votes
2 answers
647 views

Serial Interfaces - Why USB and PCIe require PHY while e.g. SPI does not require?

I'm trying to understand the reason why USB and PCIe (considering a single lane) can achieve higher data rates than e.g. SPI, I2C, UART. The reason may be the better handling of signal impairments at ...
user avatar
0 votes
0 answers
45 views

USB-C cable PCB

I'm trying to emulate USB cable by FFC and Flat connectors ( I-PEX_20535-020E-02 ) but I don't know if it is possible use 2 layers for the pcb design. In TI Superspeed guides (SLLA414) they advice you ...
user avatar
  • 330
0 votes
1 answer
82 views

What is the Test ID number of the USB7216 USB Hub chip

I am using the Microchip USB7216 USB 3.2 Hub chip in my design. I would like to know the TID number of this part. I have looked in the datasheet, on the manufacturer's website, and the internet in ...
user avatar
  • 26.1k
1 vote
0 answers
40 views

STM32H743 with USB HS, FUSB2805 not detected

I have a custom board with STM32H743VIT6 connected to an external USB HS PHY, the FUSB2805MLX. I am trying to run a bare minimum example setup in STM32CubeMx. Just including a USB HS connection and ...
user avatar
  • 11
0 votes
0 answers
45 views

USB Data Line Current Value

I am designing USB2.0 hardware input but i don't have enough space on my PCB area. I searched many site but I cant find any information about D+ D- data lines power consumption. I am using 15R ...
user avatar
  • 103
0 votes
2 answers
103 views

Can I remove the power wires of USB 3.0 and still use data wires? [closed]

So I have this SATA to USB converter for 2.5 inch HDD I want to cut away the power port (5v) and use the remaining data port with an separately powered (12v) 3.5 inch HDD. I was wondering if this ...
user avatar
0 votes
1 answer
41 views

USB to 2.4v receiver power reducer [closed]

I am trying to power a small receiver with a USB pack it shows 5v coming from the USB and it says max 3.5v coming into the receiver. I know somewhere there is an inline reducer to step down as not to ...
user avatar
0 votes
1 answer
84 views

How to connect USB to an ATmega328p?

I'm making a board that requires an ATmega328P to respond to commands from a computer. It needs to be connected with USB. I am new to this and trying to figure out how to best do this. I know I'll ...
user avatar
  • 1
2 votes
1 answer
46 views

FFC USB Board Design

I'm working on two little pcbs to emulate a USB-C usb A cable by FFC. In the future I would like this designs on other PCB avoiding USB wires and connectors. For this, I want to test it with the next ...
user avatar
  • 330
0 votes
0 answers
45 views

usbc extension cable pinout

Does anyone know where I could find the pinout for a USB Type C male to USB Type C female cable? I have found several "extension" cables on amazon such as this one : https://www.amazon.com/...
user avatar
1 vote
0 answers
31 views

AVR MCUs parametric search shows number of USB modules but no USB interface

I am looking for AVR MCUs that have USB 2.0 (or greater) capabilities. Using their website for Parametric search, I see that some MCUs have USB modules, but they are not listed as MCUs that have a USB ...
user avatar
1 vote
0 answers
33 views

2 USB cable stripped wires vs black unstripped wire?

Here is my simple little project , I have bought these 2 very long cables, USB cables, but with time the micro USB side which you connect to devices has been damaged on both of them, the USB connector ...
user avatar
  • 11
1 vote
1 answer
63 views

HAL USB device library transfer complete callback (USB MIDI adaption)

I have been able to implement Zac Rogers USB MIDI adaptation of the Cube MX USB device middleware: https://github.com/zacrogers/blue_usb_midi I can send USB midi messages on both F103 and F411. It ...
user avatar
1 vote
0 answers
25 views

Using single lane superspeed(usb 3)part with usb c port

I need to use usb c connector for usb 3.0 chips(slave) only supports single superspeed lane. master can be single (usb a type, using a to c cable) or dual superspeed lane(usb c type). How can i ...
user avatar
  • 11
0 votes
1 answer
34 views

How to charge properly 3S Li-Ion battery pack?

I'm building a 3S 18650 Li-ion battery pack, which will be used for fast charging and discharging. Unfortunately, I can't find a 3S battery charging board that is commercially available. I found out ...
user avatar
2 votes
1 answer
77 views

What is this port, 4 holes, 2x1.8v pairs

I am trying to reverse engineer a cheap Chinese Hi3518ev200 based camera for quite some time now. I have successfully located the UART used for the serial console (3 pins lower left on the picture), ...
user avatar
  • 121

1
2 3 4 5
63