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

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0answers
24 views

System not working as expected - resistance measurement

I found a problem while measuring the resistance from PCB1. When both the FETs are enabled on System 1,the resistance is measured. PCB1 is powered from USB port 1 and system 1 is powered from ac-dc ...
0
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0answers
30 views

Switching USB connections between two devices?

I currently have plans to convert a keyboard to bluetooth using a bluefruit module, but I would also like to have a switch to make it wired if I ever want to plug it in. The bluefruit module is being ...
0
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2answers
54 views

Can I replace a mini USB socket with a micro USB socket? [on hold]

I have an old PSP which has a mini USB socket. This creates many unnecessary problems. I tried adapters but they are too expensive and don't last long. Will soldering a micro USB socket in it create ...
0
votes
1answer
69 views

Switching between two power supplies with a P channel Mosfet, Is VGS or VDS a problem?

So I am using the following circuit to switch between VIN 0-30v and USBVIN 5v. I thought I found the ideal solution until I realised the FET in the schematic only has a max VGS of 8V. But I don't ...
0
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0answers
22 views

Device descriptor stall on windows, works on linux microchip mla

I'm designing a USB device with Microchip's MLA v2015-08-10 on a PIC24FJ128GB202. The device works as expected on my Fedora 23 Linux system. It enumerates and is recognized as a HID device. On ...
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1answer
55 views

How do I change the supply voltage on my phone USB port? [on hold]

Is there any program or application that can change the supply voltage on an Android phone so that it's something else than 5 volts?
3
votes
1answer
42 views

Is UL approval at all possible for low voltage USB and network LAN Cat6 patch cables

I am from a European distributor. Some of our customers, who export to the US are asking for UL approved Cat6 and USB patch cables. Is it even possible to UL approve these low volatage cables? i.e is ...
0
votes
1answer
60 views

How to connect micro-USB to voltage regulator for MSP430 microcontroller?

I am going to use a micro-USB to power my MSP430 microcontroller. That means I only need the 5v and the GROUND pin. However, after discussing that the other pins should be untouched.. my friend said ...
1
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1answer
28 views

Programming USB OTG PIC32 through USB in MPLAB

I have a PIC32 that has USB OTG. How would I program it through a USB cable in MPLAB? Does it work out of the box of does it need additional software.
0
votes
1answer
28 views

STM32F439 CDC driver, is using UART required?

So, most of the examples use USB CDC driver and they bridge UART. I'm not embedded guy and learning the stuff one by one. So, I understand UART... But I'm a bit confused how this bridging works. Is ...
1
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1answer
37 views

USB Connector Current Rating for Charging

I have heard it mentioned that the current rating for a USB charger is dependent on the current rating of the USB port itself; ie a Type A connector has to be rated for 2A on a charger that says it ...
0
votes
3answers
125 views

Can I charge a 12v toy with USB? [closed]

I have this small palm sized toy drone. It uses a 'charger' which houses 8 AA alkaline batteries. The charger plugs into the drone and the charger is activated by a toggle switch. I want to replace ...
0
votes
2answers
86 views

How to connect multiple micro-controllers' USB ports on the same PCB?

I'm designing a PCB with 3 Atmel ATmega16U4-AU micro-controllers on it. I will be programming them through SPI. Therefore, I will not be using D+ and D- ports on the USB interface. Then how do I ...
6
votes
2answers
84 views

5V tolerance on VBUS sensing input

I am designing a device around the STM32L476. My device is primarily battery-powered, but has a USB port that, when plugged, I want to use as an alternative power source (through a 3.3V regulator) to ...
0
votes
2answers
91 views

Confused about how microcontroller board and computer communicate

i recently got myself FRDM K64F board and got myself occupied with the following questions : Does the compiled hex code i send to my board has to go to the uart chip prior going into ...
0
votes
1answer
53 views

How to “frankenstine” wires?

How do I make a different usb wire type out of two different usb wires? For example, say I have two standard usb-to-micro-usb wires and I want to make one usb-to-usb and then one ...
-2
votes
1answer
37 views

What is the difference between “FS Device”, “FS Device/Host/OTG”, and “HS Device/Host/OTG”?

I'm going to buy a PIC32 which has inbuilt USB support. What is the difference between "FS Device", "FS Device/Host/OTG", and "HS Device/Host/OTG"? Am I right in thinking that the "OTG" aka "on the ...
0
votes
1answer
25 views

5v usb cable to power a 2AA Kitchen Scale [closed]

This is my first question and I'm a total beginner at this, so, please be kind :D I have a kitchen scale that eats up 2AA batteries every 2-3 days, so I thought to power it via a USB wall charger ...
0
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2answers
41 views

Adding an on/off switch to an USB charger [closed]

I was wondering if it is possible to wire an on/off switch into the cable of a wall-wart USB power charger as easily as it is to wire an on/off switch into a regular power cable? Or are there ...
0
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0answers
35 views

How to boost a small solar panel by a few volts?

I have a 4v solar panel, and I have load that takes 5v. So, how can I just increase the solar panel by 1 volt? Thanks.
0
votes
3answers
38 views

Simple USB powered PIR sensor with LED attached to it (no arduino)

I'm new here and I'm re-new in electronic hence why I'm seeking for some help. Last time I touched a breadboard with a transistor was 10 years ago. So, here's my problem and the problem to the ...
0
votes
0answers
28 views

Is there a usb controller IC which give MCU USB capability?

It is disappointed that the MCU I want to use in my project does not have USB controller nor USB PHY capability. Can I simply add one standalone USB controller IC? I see device like FT2322h can ...
0
votes
2answers
43 views

Can I use a point-of-load converter for providing USB power?

I'm designing a power supply that I would like to have a USB power output for charging/powering USB devices. In an effort to reduce risk and design time, I'm looking at mounting a DC/DC converter on ...
0
votes
1answer
38 views

Raspberry Pi 2 to arduino RF Serial link with USB to Serial TTL Converter

This is my first question here. I want to have a communication channel which will use a 433 MHz RF TX-RX pair. I want to use a Raspberry Pi 2 as a transmitter and an Arduino Mega as a receiver. Is it ...
0
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0answers
53 views

Feasibility of HID gyroscope

I'd like to add a gyroscope to my phone because, like many other from china, it doesn't have a gyroscope. I'd mainly like to use it for VR (with cardboard). How feasible do you think it is to create ...
0
votes
1answer
52 views

Regulating voltage so USB works with module

I recently purchased this GSM/GPS module. I would like to power this module via a USB cable but can see that it has varying input voltages. So bearing in mind that USB is 5V and that I'm an ...
1
vote
1answer
59 views

USB 2.0 layout on 2-layer board

I have laid out this board that includes (among other lower speed connections) a 1 upstream and 2 downstream ports on a 0.5mm FR4. The USB differential traces are 0.6mm wide with 0.15mm spacing ...
2
votes
1answer
88 views

rx_polarity inversion in USB3.x

As per USB3.x specification there is provision of rx_polarity_inversion can any one exactly says, what is the reason behind it? Edit: Normally connection of ...
0
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0answers
22 views

AM3358 Usb type C support?

Does the AM3358BZCZ100 have support for USB type C? or is USB type C just like any other USB interface, I am currently looking through the data sheet so probably will find it there.
3
votes
2answers
78 views

Waterproofing USB port

Recently Samsung came out with the new Galaxy and Edge phones which are advertised as IP68 rated.The mircro USB ports on these phones are completely exposed, yet are still IP68 rated. My question is, ...
-1
votes
2answers
110 views

How to program a microcontroller via USB using JTAG? [closed]

I have some hard time understanding JTAG for programming. I have an mcu that can only be programmed via JTAG. What are some easy chips to start with in order to program an mcu via JTAG? I suppose I ...
0
votes
1answer
22 views

Digispark Attiny85 dev-board - Program via USB or UART/serial converter?

How do I program those Chinese ATtiny85 Digispark clones? Are they programmable via USB or do I have to use a USB to serial converter to program them? For example, this unit.
3
votes
2answers
76 views

Likely consequences of slightly exceeding 500mA USB current

As we know, a USB 2.0 device, once it has properly negotiated with the host, is allowed to draw 500mA. Suppose that you are designing such a device, and your input current limiter chip is tuned by a ...
0
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0answers
31 views

Maximum SPI clock frequency of CP2130 USB-SPI bridge

I have a board with SMT32F103 MCU and CP2130 chip connected to MCU's SPI2 channel. CP2130 is master only, so I configure MCU's SPI to act as a slave with software slave management. There are no more ...
1
vote
0answers
21 views

USB HUB reboots when external power is applied - normal or abnormal? [migrated]

Equipment: I have a StartTech.com 7-port USB 3.0 HUB plugged into a PC. There are seven devices plugged into the hub, and I'm running the 12VDC external power to the HUB as well. The HUB is plugged ...
1
vote
1answer
54 views

Are there downsides in using cat5 / cat5e cable for USB 3.0 connection?

It's been pointed out many times that USB 2.0 can (more or less) safely be used with cat5/5e cables and connectors, at least as long as these requirements are met: Data pins are on its own twisted ...
0
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2answers
63 views

Ambient LED Project

I'm working on mounting LED strips to my entertainment set up and part of it involves mounting strips to the back of my TV. I want to power the LEDs via a USB port found on the back of my TV. I'm ...
1
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0answers
20 views

Circuit for auto repeat switch off/on USB Data-

I recently aquired an APC UPS and connected it to my (Mac) server through USB. However, the load percentage is only updated (via pmset -g ps) when unplugging/plugging the USB cable. I found out it's ...
0
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2answers
55 views

Can I use a USB connector/plug for RGB Led Strip

So I have an RGB Led Strip that requires power (3 Colours and the ground). In total it draws about 1A @ 12V = 12W. Could a USB socket be used to handle this? Otherwise I'm simply seeking a neat and ...
0
votes
1answer
22 views

best USBD mode for transceiving low rate data in LPC11u68 based on LPCOPEN

I'm trying to use lpc11u68 for transceiving data between PC as host & MCU as a slave,Data rate is about some KBPS,plug & play ability (no driver need)is desired but not necessary,Simple ...
4
votes
1answer
47 views

FCC-approval and “modular” integration

I see that a PCB requires certification even if it incorporates a certified RF module, so EMC tests for spurious emissions will still be needed. Is FCC-approval needed if a Raspberry Pi is ...
0
votes
1answer
34 views

TVS unintentionally shorting on USB?

I had a very peculiar situation on a PCB I am working on, and the only possibility I can think of is that my assembler installed the wrong chip on my board. I'd like to present it to the forum to see ...
1
vote
1answer
55 views

GL850 USB hub with or without capacitors?

I'm looking at two different USB 2.0 hubs which both use the GL850. This is Hub 1: This is Hub 2: Both take an external power source but Hub 1 uses four 220uF caps. Does anyone know why a cap ...
1
vote
0answers
47 views

Transzorb for MCP73831 USB LiIon Charger?

The datasheet of MCP73831 (a small LiIon charger device) recommends a transzorb on the USB power input (VDD) for input over voltage protection. See Section 6.1.1.2. Absolute maximum ratings for VDD ...
0
votes
0answers
25 views

USB 1.0 Host speed negotiation to USB 2.0 Device

What is the negotiation sequence of a Low Speed (USB 1.0) Host connected to a High Speed (USB 2.0 Device) ? On connection the Device pulls up the D+. If this was HS/FS the Host would pull the D+ down ...
0
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1answer
48 views

Down sides/Cons to Dual-Sided USB connectors?

Do dual-sided USB connectors have inferior qualities compared with single-sided e.g. less mechanically reliable or reduced speed? From reading Why do USB connectors only fit one way? it seems that ...
0
votes
1answer
58 views

10Mbs USB to serial communication

I want to transfer data from a full duplex serial device (TTL) to the PC. The data rate is 10Mbs , i am investigating potential solution. I can add a level converter like max232. I have 2 questions: ...
3
votes
1answer
52 views

Kick-off Spread Spectrum Clocking

Need of SSC: Spread spectrum clocking (SSC) is a special way to reduce the radiated emissions of digital clock signals. These levels or energy is radiated and therefore this is where a potential EMI ...
2
votes
1answer
165 views

Looking for a male USB B connector [closed]

I'm trying to get a connector that will connect another product as a sort of 'daughter board'. This thing has the old USB B connector on it and what I'd like to do is back it up to this connector and ...
0
votes
1answer
41 views

Multiple signals over single RJ-45 cable

I need to set up a Raspberry Pi system with remote storage, but only have access to a single RJ-45 cable. This limitation is so the system may be replaced in the future, without having to change the ...