Questions tagged [usb]
USB is Universal Serial Bus. If your question relates to a specific chip, please mention it in your question.
3,633
questions
0
votes
2
answers
42
views
When wiring up a usb port without a hub, how do you wire up a current limit switch?
I'm challenging myself to make a CM4 carrierboard, mostly by just taking the bits of the CM4 IO board that I'm interested in and leaving the rest.
I've seen that the CM4 only has a single USB2 "...
- 243
0
votes
2
answers
40
views
What exactly makes the SET_ADDRESS command fail in my situation?
TLDR: Can USB packets be transmitted between host and device, even if a possible hardware problem exists as evidenced by a USB error -71?
I am working on a custom ...
5
votes
2
answers
490
views
Can I use Cat 6A to create a USB B 3.0 Superspeed?
I'm trying to put my PC 10 meters away from me, and USB 3.0 active extenders have failed me due to interference with my 2 HDMI Cat 6A cables that shared the skirting board with it. I'm trying to find ...
- 153
0
votes
1
answer
31
views
USB breakout board for turning off device - SHIELD help needed
Currently I design a breakout board which I plan to introduce between USB device (e.g. keyboard) and USB host (e.g. computer). For reference take a look at picture below.
On breakout board there is ...
3
votes
1
answer
278
views
What difference does the USB-C connector make what orientation the cable connected to it is now?
I read a document from FTDI about USB Power Delivery where it is written that the connector (USB Plug) can determine the orientation of the cable by the CC pins, but I can’t find any information about ...
-1
votes
0
answers
56
views
Power the board via VBUS only [closed]
I am working on a project, where one of the main goals is to implement a USB-powered board (no external power supply, only via VBUS). The board will include Cyclone IV FPGA, FT600Q USB FIFO chip, a ...
- 45
1
vote
0
answers
47
views
Incomprehensible protocol overhead present in Table 5-10 of USB 2.0 Standard
The USB 2.0 Standard features a table (table 5-10) where high-speed bulk transaction limits are computed.
The table cites a "Protocol overhead" of 55 bytes, computed as follows.
(3x4 SYNC ...
- 11
1
vote
1
answer
123
views
How can I select one of two identical USB power sources while blocking out the other?
I am trying to design a keyboard with two USB-C inputs that connect to host. I decided on using a HD3SS6126 for switching logic.
HD3SS6126 datasheet.
I would like to make it so that when one of the ...
- 11
1
vote
0
answers
44
views
How do i trick a Powerbank for detection of USB?
I builtd and LED light panel that uses LED strips. Currently using 2 wire USB cable to power it via Powerbank.
Currently you need to turn the powerbank on and then it provides power to the LED when ...
- 21
1
vote
3
answers
104
views
How to boost USB power delivery
I have an old Raspberry Pi 3, which I believe offers 4x USB 2.0 ports with max 1.2A in total, according to documentation. I actually only use one port but for an SSD NVMe (using a USB housing) which ...
- 1,407
0
votes
1
answer
41
views
USB3300: ULPI link reports "Failed PLL lock" error upon booting into Petalinux
Currently debugging the USB2.0 transceiver or PHY chip (USB3300) that seem to fail to have the ULPI link lock the transmitted 60MHz clock signal (PLL lock failed error). I found that the chip's ...
0
votes
0
answers
33
views
Toy modification, remote control, battery to usb
i would like to modify a few toys to change it from manually pressing 1 or 2 buttons on the toys to using remote (IR?) control. and I would like to change it from battery driven to usb and be able to ...
0
votes
1
answer
89
views
Is AC power in India unstable? [closed]
I often feel electricity from the chargers I use in India.
I think it is because the building is not grounded. Do most people have similar experiences?
What should I consider in my design to solve ...
0
votes
1
answer
48
views
USB-C Alternate Mode - ensure no activity on TX / RX pins during enumeration?
I am working on a project that will consist of a USB-C host and device. The idea is that the host will use the alternate mode pins of a USB-C connector to drive analog signals to peripherals on the ...
- 1
1
vote
0
answers
35
views
High latency at low data rates w/USB to Ethernet Adapter [closed]
We have designed a custom board that utilizes a USB Micro connector interface. We currently connect to the USB Micro connector using a USB Micro to Ethernet adapter to send data between our custom ...
- 137
0
votes
1
answer
27
views
Auto switch power source for RPi Pico type board
I'm developing a MIDI controller around a RPi Pico type board (docs here), which doesn't support simultaneous powering through USB and a separate supply. VBUS and VSYS are outputs if powered by USB ...
- 389
0
votes
0
answers
51
views
STM32H750 isochronous missing packets
I am making a USB HS open-source sound card using STM32H750. Essentially, I got the USB audio class template and modified it to USB audio class 2. And, I have several problems with packets being ...
- 1,141
1
vote
3
answers
132
views
Provide 5V and 5A through USB-C
I need to power a Raspberry Pi 4 using an ATX power supply. Unfortunately, it needs to be done this way for reasons beyond my control.
My solution was to connect a +5V and a ground wire of the power ...
- 13
0
votes
0
answers
31
views
Questions Related to GNSS with ATtiny ICs
A while back I was given a few ATtiny 804s. I've been looking to build a small GNSS device as I wanted to get some raw GPX data without using a phone. I thought I might be able to use the ATtiny 804s ...
22
votes
2
answers
6k
views
How are USB-C cables so thin?
Looking at the plug of a USB-C cable, there are 24 different pins. With a Micro USB cable, each pin corresponds to one wire inside the cable. In my understanding, this means that a USB-C to USB-C ...
- 323
2
votes
1
answer
72
views
STM32H750: Reset timer on HS USB SOF
I am making a sound card with STM32H750 and USB3300. I am using standard Stm32CubeMX USB driver.
To do that, I need to track the number of I2S sample rate clocks per SOF. The idea is to use TIM5 as a ...
- 1,141
0
votes
1
answer
31
views
ESP32 with CH343 serial timeouts on flash but monitor works
I'm trying to flash an ESP32 over a CH343 USB to UART device using an M2 Mac running Sonoma. When I connect over USB the device enumerates, I am able to open a serial monitor, and I can even check the ...
- 362
0
votes
1
answer
41
views
Can I use a 16 MHz HSE for USB and USB DFU on an STM32F103?
I'm working on a PCB with an STM32F103C8 and a 16 MHz HSE.
USB FS is working as intended so far (I can send USB HID keystrokes).
I haven't tried flashing it using USB DFU yet.
I read in PM0075 (page 9)...
- 157
0
votes
0
answers
54
views
Please review my usb lipo charging circuit
I've followed a tutorial on YouTube on how to make a USB charging and powering circuit for some mobile device. I decided to change up some parts because they were either too expensive or had too many ...
- 21
0
votes
1
answer
47
views
Powering 5 V mini fan through laptop USB?
I recently bought some 5 V fans, which are super small, they work well with a battery and Arduino 5 V power supply, but when I connect it directly to the USB port in my laptop, it does not work. But ...
- 1
0
votes
1
answer
74
views
Type P MOSFET to switch voltage bus
I'm working on a project where I'm using the NTE0505MC (5V, 200mA) component to generate an isolated 5V output. Connected to the output of the NTE0505 are several components, and a Schottky diode is ...
- 179
1
vote
0
answers
36
views
USB device stops working for some reason [closed]
In my custom boat project i am using a Raspbery Pi. In order to get an engine telemetry (RPM and temperature) i connected a diagnostic adapter(ELM327 or "vag com kkl") to the engine OBD2 ...
- 111
0
votes
1
answer
80
views
How to create a PC version of a PCB project made for RP4
I want to create a PC version of a PCB project I made for Raspberry Pi 4.
It is a simple PCB of a 5-button micropad that connects to 5 GPIO Pins (+1 3.3V GPIO for Pull UP) on the RP and using the ...
- 23
10
votes
1
answer
1k
views
Can I replace this resistor (in USB adapter that plugs to mains) with this other resistor?
I would just test this instead of asking here, but because this goes to mains, dangerous voltages and all that, I prefer to be safe than sorry.
An old USB adapter stopped working, and I finally took ...
- 243
4
votes
1
answer
121
views
USB 2.0 bus issues with signal integrity
I have a USB 2.0 Bus that has errors with certain cable/hub combinations. Looking at the signals, they look awful (1GHz differential probe 50Ω).
As far as routing goes, the total length is about 4&...
- 87.1k
3
votes
3
answers
252
views
Limiting voltage on voltage monitoring pin
Question:
How do I limit the voltage on a voltage monitoring pin to 28 V DC (due to voltage rating) when the power rail voltage to be measured may go up to 48 V DC continuous?
Are there DC-DC ...
- 31
2
votes
4
answers
225
views
Confusion with the meaning of virtual com port
As far as I read, plugging a USB mouse into a PC is not creating a virtual port; but plugging a serial to USB converter does.
This is very confusing for me since from PC operating system's point of ...
- 371
0
votes
1
answer
72
views
USB cables being affected by manufacturing equipment [closed]
I am an IT guy, who enjoys learning about some of the electrical engineering side of things, but I don't have a good grasp of the jargon.
We have a client with about 40 different smaller production ...
0
votes
1
answer
111
views
USB data does not work on my PCB [closed]
I've build a PCB based on RP2040 microcontroller. A modified version of PicoDVI board - with added memory chip.
The board works fine, with just one problem - it is not being detected when plugged to a ...
- 171
15
votes
3
answers
3k
views
USB A mechanical orientation?
This concerns a USB A socket on a PCB.
Is there a standard or preferred orientation of the polarization tab, either up or down?
The picture shows one with tab towards the top
- 14.2k
0
votes
1
answer
69
views
Replace this USB power board [closed]
I have broken this board, its for USB powered lamp. I presume it is a power conditioner for usb power... As its before the light color/control board. Im not sure if it was USB or USB C - I presume its ...
- 103
-1
votes
1
answer
66
views
5V on DP and DM pins on FT232RL?
Can I apply 5 volts to the DP and DM pins of the FT232RL, given that the technical sheet says that the maximum voltage of these pins is up to 3.8 volts?
4
votes
2
answers
547
views
USB Data communication issue on a panelized pcba hardware test platform
I need some help..
I developed a test platform for the hardware tests of an electronic board panelized in sets of 10. The boards are placed on the test platform in their panelized form. As shown in ...
- 195
0
votes
2
answers
63
views
Do FT232 come pre-programmed out of the package?
I'm working on a board which requires USB serial communication. For this I want to use an FT232RNL, however I'd like to know if I need to program it before I install it on the board. Also, do I need ...
- 31
2
votes
2
answers
52
views
12V through USB Type C without PD
Can I get 12V to my system through USB type C without PD or configuration CC lines or Using CC controller?
If yes how can I do that .
- 21
2
votes
4
answers
162
views
How is CRC5 calculated in detail for a USB token?
How is CRC5 calculated in detail for a USB token?
...
- 23
2
votes
1
answer
79
views
FT230X using USB-C receptacle not working for data transfer
I have tried to add a USB-C connection to my PCBA solely for data transfer.
I have used a FT230XQ-R microchip (Datasheet) and followed their uploaded example for a USB-C receptacle. I have now ...
- 43
0
votes
0
answers
74
views
Purpose of NPN transistors in this ESP32 circuit [duplicate]
I am wondering what is the purpose of the two NPN transistors Q4 in the circuit below.
(full circuit schematic)
In this circuit, which is from an eval board for the ESP32-S3 microcontroller, ...
- 720
0
votes
0
answers
28
views
DC isolation - 3 separate circuits with same power source and shared I2C
I am trying to build one small project and based on the needs I need to isolate few components but also keep them connected using I2C. I was doing a research and found few DC DC isolator converters ...
1
vote
1
answer
51
views
A simple visual indicator (LED light?) when a USB fan is on
I have a USB fan, some distance away from me, which I use occasionally. It's plugged into a charger and it has a manual switch. I sometimes forget to turn it off, because it's very quiet so I can't ...
- 265
2
votes
2
answers
91
views
Home made USB 2.0 device switcher (for mouse/keyboard only)
I did buy some off the shelf ones, but they seem to fail after a few months and or screwing up the USB ports.
I opened the switch box up and noticed that the two power lines were always connected to ...
- 21
1
vote
0
answers
70
views
Making audio signals imitate USB flash drives [closed]
If there is a USB port designed for USB flash drives that plays the audio files in that drive when it is connected --such as the ones commonly found in cars-- is there any practical way to turn an ...
- 43
0
votes
0
answers
29
views
ESP32, BQ25895 sharing usb data lines
Im building a portable device with a ESP32-S3 which will be interfaced with a SD card, and a BQ25895 charge controller. The ESP32 will connect to the computer as a mass storage device. The BQ25895 ...
1
vote
0
answers
97
views
Flashing ESP32-S3 directly over USB
Since the ESP32-S3 offers USB-OTG, am I right if I assume that I only need to turn on the chip by pulling EN to high (3.3V) and then connecting it via USB to my PC? Am I then able to flash it via ...
- 420
0
votes
1
answer
33
views
USB bank + capacitor for flash gun
I have a camera flash (Godox TT350), which typically takes 2 AA cells. These cells do not last long, so I bought some dummy cells, which are connected to a USB plug.
The USB is inserted into a battery ...
