Questions tagged [usb-device]
Quesions about the design of USB devices that connect to a USB host, such as a PC.
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USB4 minimum speed requirements
Based on what I'm reading in the USB4 V2 spec (section 2.1.1.4), in addition to less technical references I've been able to find online, all USB4 hosts, hubs, and devices are required to support 20G (...
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What does a USB device need to do so that the host device can sleep?
I am using an ATmega32u4 that is connected semi-permanently to a mobile Android device (specifically, a keyboard connected to a phone).
While the device is connected and USB is enabled on the ...
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Can a USB 1.0 low speed device negotiate for 500 mA of current from a host?
It is my understanding that a USB 2.0 High Speed device can never negotiate for more than 500 mA of current, even if it is connected to USB 3.0 Super Speed host. That is because the Configuration ...
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Android phone/tablet and computer does not recognize the 2d lidar connected by type-C [closed]
We are using a lslidar m10 which has a type C interface. It can be connected to the USB A port on a computer and work fine.
Now we look to use the lidar with an android tablet/phone which only has a ...
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Want to know blown out diode value of USB device
I have a PTZ camera which has 9-pin USB B device. When I plug into to the USB it shows the error power surge. I knew something was burned out and opened the device to check and found out that one of ...
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USB ESD Protection with the NUF2042XV6T1G IC
I have been trying to figure out how exactly I should connect the NUF2042XV6T1G IC to my USB data lines. From what I understand, usually a reverse biased transile diode is connected between the data ...
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USB Port Design with ESD/Overcurrent Protection
I am working on a small project in which I use a CH340 to communicate with an MCU, but during prototyping I probably should have a way to protect the controlling computer's USB port from shorts. I ...
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USB-PD over USB-A
I have a power adapter from Samsung which supports an output of 5.0V 2.0A or 9.0V 1.67A. The adapter has a USB-A output and fast charges my S10 at 9V. Can USB-A be used for USB-PD?
I also have a ...
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USB2244 card power is never supplied and USB port is not detected [closed]
I have been trying to use the USB2244 on a board but I can't seem to get it working and I am not sure what the problem is. I went over and over the datasheet but can't seem to figure out what I'm ...
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IC to detect when connected to DCP vs SDP/BQ24392 Wiring Help
I'm designing a device using the MCP73871-2CC, which I would like to be able to vary its charge rate via the SEL pin. For this purpose, I think that an IC would be needed that could detect the ...
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Does the quality of USB cable affect the power drawn?
I was wondering how the power drawn is affected by different cable? I tested two different types: A USB cable plugged to a USB digital tester which showed a power of 4.88 V and 2A drawn, whereas the ...
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Nandland Go Board - Diamond Programmer
I'm trying to program my first FPGA with the Nandland Go Board on Windows 11.
I've followed all the instructions in these tutorial videos:
https://youtu.be/nfB8-8JfVFE
https://youtu.be/l_eo21vHxw0
...
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How does a USB HID gamepad specify button codes?
I'm working on a device emulating a USB HID gamepad with 32 buttons. This is the basic Report Descriptor I created
...
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Checking voltage of battery with a USB connector
I soldered two wires on female USB type A pins,one wire to ground and the other to the VCC pin.
I was trying to check the battery voltage of the li-ion battery in my flashlight,
I connected the a ...
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LTE SC206E Smart Module acting as USB host and device
We have a requirement such that SC206E should act as a device when USB cable is connected to
J12 for programming ,otherwise it acts as a host. For this purpose we have implemented the circuit as shown ...
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What constitutes a packet a Wireshark USB bus capture of an isochronous endpoint?
I am working with a USB device which uses UAC to transfer audio data to the USB host and it does this through an isochronous endpoint. I understand that these endpoints are polled on regular intervals ...
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How to get USB 3.x power but with data limited to USB 2.0 HS?
I am designing a device with a few interesting requirements. Due to power requirements, we need to draw 900mA, but due to isolation requirements, we're limited to the 480Mbps rate for our primary ...
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Streaming 30 MByte/s into a PC using an FT232H?
I want to bring a continuous 30 MByte/s stream of 8-bit values from parallel-output ADC (AD9283) into the memory of a standard PC (laptop under Windows 10 if possible). My software does real-time ...
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Using only USB Type C signals without USB2.0 Signals
Need your help regarding SC200E USB. As per my understanding SC200E supports both USB2.0 and USB Type C.
My question is can we use it separately.
I mean we need to connect the USB2.0 signals of SC200E ...
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The receiver sends correct but too much information to the keyboard with STM32 nRF24
I have a problem with keyboard hid. I did remote control with STM32 transceiver nRF24. My problems that receiver true receiving incoming data but too much text. Problems that:
...
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Can USB-to-SERIAL dongle be used to drive an RS-485 transceiver?
Pictured below is a simple arrangement used to read the Temperature sensor from the PC. Standard/Protocol is MODBUS RTU RS-485 Half-Duplex.
I've used this arrangement with both modpoll.exe and ...
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Convert USB (HID) Full Speed to Low Speed
I want to connect a KVM-over-IP device to the console of my USB KVM switch to make it IP capable. The KVM-over-IP device offers a USB Full Speed composite device with keyboard and mouse subdevices, ...
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USB connection and reconnection issue
I have upgraded a design with a USB2412 to a design with a USB2514Bi chip to have more USB ports available.
During testing we discovered the device works like expected when we connect it to a USB A ...
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USB 2.0 Pogo connect to programmer board across 5mm gap
I am looking to make a 5mm connection from a programmer board to another board with USB 2.0 on it through some pogo pins. Could something like this work for the high speed over a short distance? Any ...
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Configuration of USB Hub
I'm planning to design a USB hub and planned to select this device
My design questions:
From the datasheet, if the SS signals (Tx and Rx signals) for the downstream ports are not used, then it is ...
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USB Type A with "PD Detect" pin. How is this leveraged?
I'm looking into using a USB 3.1 type-A port (ref: 632121300001) and its male counterpart that comes with a "PD DETECT" pin. I'm looking to make a USB-A to USB-C cable.
I might be missing ...
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Using a ground plane for my USB front IO
I've been conducting a long-running personal project, designing and building a custom PC case. I've got round to the front IO panel and figured to design and make the circuitry myself instead of ...
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Choose resistor for USB cable to mimic 1.5A load
I have a USB A 3.0 cable going from a PC to a USB testing device. In the future, a load will be between the pc and tester that will draw 1.5 amps. For now, I need to mimic that draw so that I can ...
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How do devices know how much power draw a usb cable can support?
This has been a little confusing.
I have cables that can support 5V-3A for both USB 2 and 3.
If I put together a type C to type A cable, the specs mandate the Default USB Type-C Current Rp resistor (...
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Custom HID UPS not detected by UPower in Linux
My original question: https://stackoverflow.com/questions/75910694/custom-hid-ups-the-host-does-not-update-the-data-from-reports
I'm looking to build a USB HID device (uninterruptible power supply) ...
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What are the chips to build usb device? [closed]
I want to make some device, that should just do one thing - send few values - x,y and z via usb, so at pc end, for example there will be a driver for that device, which some program can access and ...
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Do multiple USB 1.1 devices on a bus require a hub?
Can I simply attach multiple USB1.1 slave devices to a bus like I can with I2C (config A), or does the spec require a USB hub IC (config B)? Power in this application will come from a separate bus.
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How can I reduce the output voltage in a simple way?
I want to connect my old smartphone (Galaxy S4) directly to a charger without battery.
I want to connect plus and minus pins, so I need 3.8 V input, but the charger gives 5 V.
What is the best and ...
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USB UFP and DFP - differences
How to understand or differentiate between a USB upstream-facing port and a downstream-facing port?
Just want to understand it to place the resistors on the CCx pins in case of using a Type-C ...
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Basic USB Endpoint0 configuration error ATmega32u2
I've been trying to make a simple custom usb device class for a project based on the Atmega32u2. I have been trying to get a usb device enumerated, but I can't get endpoint 0 properly configured. I ...
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Can unused USB Type C pins be shorted together?
Can the unused USB Type C connector pins be shorted together?
Can someone please verify if my terminations for the connector pins are correct or do they require modifications?
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How to determine the maximum charging output of a QI wireless charging coil and circuit board?
I purchased a 20-watt 3-coil QI wireless charging coil and PCB recently (see image with specs below) and I want to power it via the USB-C header and preferably a USB-C to USB-C cable. The USB port on ...
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USB host design
I'm trying to design a USB host device with an RP2040.
I want to power my circuit using a USB-C connector using a phone charger or a power brick. The device will be powering external devices using a ...
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How to secure USB connections mechanically
What is the recommended way to secure USB Type A connections to their ports to protect against vibration (such as from a human walking, or if it was in a vehicle), in manner that will last at least ...
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When to choose Class I vs Class II AC to DC power supply?
Feels like I'm missing something obvious here, but when is it appropriate to use a Class I vs a Class II AC to DC power supply for a commercial electronic device? Should Class II only be used when the ...
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Terminating resistor for SL2.1A controller?
I'm currently making PCB with an integrated USB hub that will use an SL2.1A chip and I'm wondering if I should use any kind of terminating resistors on data lines? I read the datasheet and couldn't ...
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USB Hub Self-Powered using USB Type C
I'm designing a board based on a USB Hub HS 2.0 that has five permanent attached ports, two of them with a high current consumption (180 mA typical, 250mA max. per device).
I would like the board to ...
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How can I allow rotation of a USB-C port if I only have a single USB 3.1 lane connected to it?
As a follow-up question to my previous question about connecting two 3.2 Gen1 Links to Type-C Connector, I learned that I can connect CC1 signal to 56K PU to VBUS and this pin-out supports one USB3.1 ...
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USB audio (TRRS) to transformer for impedance matching
I'm kind of stuck, and not really sure where to look, or what to look up.
I need to take the output of a USB audio fongle that has a single 3.5mm jack (TRRS), into a break out cable, and then need to ...
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DisplayPort Alt-Mode and USB4.0 port on USB Type-C Connector
I'm building an AMD FP7r2 based platform and I have a USB Type-C port to which I want to connect USB 4.0 signals.
The USB4.0 signals can be also used for DisplayPort (the APU supports this switch), ...
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USB port only has 3.3VDC
I have a USB bus, on a main board I am trying to break out to wire in an arduino type device. I have Identified Ground. There doesn't appear to be a 5VDC line anywhere though. There are 6 pins, 3 of ...
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Small indentation in rechargeable battery
I bought a small lamp and opened it up. I used a knife to carefully separate the top from the bottom shell and I am pretty sure I didn't insert it that much to create the two points on the left, and ...
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Do wall USB cubes have resistors in them?
Do these have resistors in them? (Picture of a Wall USB Cube Thingy) I'm really not sure the name of these, but I know some old EU ones have resistors so I wanted to know.
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What would cause a HS USB flash drive to send a different Vendor, Product in the DEVICE Descriptor and SCSI Inquiry?
I am developing an xHCI host that connects to a type A downstream connector via a HS USB 2.0 connection. I am testing it using a generic HS flash drive. The flash drive sometimes responds to the ...
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SAME70 USB CDC does not open endpoints correctly
I downloaded the stock USB CDC echo demo for ATSAME70. The device correctly enumerates over USB. I can see ttyACM0 appearing in the OS but later the demo gets stuck waiting for ...