Tagged Questions

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

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1answer
40 views

Switching between USB power and single alkaline battery

I've read the numerous other questions addressing this topic, but I'm not sure if any of them apply to my situation. I am designing a device that will run off a 3.0-3.3V supply voltage and draw no ...
0
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0answers
18 views

Advice: how to integrate minipci cards to a board design

I'm designing a pcb card for one embedded device based on a Digi iMX28 module. In the design we included a couple of minipcie sockets to add 3G and wifi cards. However, there are two flavors of ...
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0answers
35 views

Illuminate LED for Read/Write over a USB connector [on hold]

Is it possible to make a USB powered device, which can understand USB data Read/Write, i.e. when PC writes something to pen drive, it should illuminate red LED and when it's reading, green LED should ...
0
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0answers
10 views

Dont know where to connect HD AUDIO or AC-97, & USB [migrated]

I'll provide pictures so you guys can see, but basically I recently bought a new case for my pre built lenovo k330b. I cant find how I'm supposed to position the connectors. Please help me out with ...
1
vote
1answer
42 views

USB - Tolerable voltage drop

For a system I am designing I need go over 500mA limit for a very short time (30mSec). I have designed my system such that during the over 500mA period I am able to sustain my circuits using internal ...
0
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1answer
52 views

How can I use a greater USB charge current without device enumeration?

I'm designing a device with USB communications, using an STM32F105 microcontroller. It has a LiPo battery, which charges from the USB port using an LTC4077 charge controller. It will generally use a ...
2
votes
2answers
138 views

Why does Ethernet on UTP have much greater range than other modern protocols?

OCuLink, SATA, USB 3, and Displayport all provide on the order of a few Gbps per signaling pair, and are limited to a cable length of just a couple meters. Ethernet via comparable cabling provides ...
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0answers
36 views

Need 2.1 Amps from a USB wire for my lighthing conector [duplicate]

I have been working into an ipad Conector, that seems to work FINE its plugged to a 5v 12A switching power supply, this goes to my PCB where it has up to 4 outputs, each output for 1 ipad Air, up to ...
0
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2answers
46 views

Can I run a program, on an ATtiny85 with micronucleus bootloader, without usb connected?

I have managed to put micronucleus bootloader on an ATtiny85. Using it, I can successfully upload programs to my ATtiny through USB and they run as they should, as long as they are connected to USB. ...
0
votes
1answer
46 views

Shielding not connected to USB connector causes tablet restarts

I have a custom USB cable, USB type A male on one end and a DB-9 connector on the other end (only using 4 pins). The shielding of the cable is connected to the USB connector but not the DB-9 ...
2
votes
2answers
113 views

2.5mm Jack to USB data Cable

I was recently diagnosed with Type 1 diabetes. With the need to test my own blood upwards of 8 times a day I have a ton of data to keep track of. My testing unit has the ability to upload its data to ...
1
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1answer
53 views

USB current limiter and under/overvoltage protection

I know recent motherboards already provide these, but lately USB ports are also available in many different gizmos (smartphone chargers, TVs, standalone players, etc.), which I am often tempted to use ...
0
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1answer
60 views

ATtiny85. How do I burn a bootloader? What is the process?

I want to use all six I/O pins of an ATtiny85, that means also using the reset pin as an I/O pin, however, I found out that if I disable the RESET pin, I can no longer program the ATtiny using an ISP ...
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0answers
14 views

What is the difference between USB Mini A and Mini B? [migrated]

I have a bunch of USB A to Mini B cables and a single USB A to Mini A cable. I have lost track of where they come from. The two types both look exactly the same with the USB A side having a white ...
0
votes
1answer
38 views

lm2596 fixed 5 volts(usb) from 12v 10W solar panel

I have got a 10 Watt solar panel & a 10000 mha Battery bank. I plan to use the panel to charge the battery bank. I have a LM2596(variable configuration with pot), I plan to use it to charge my ...
0
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0answers
48 views

Noise on audio circuit when powered by USB

I built a simple microphone boost circuit which works well with a 3V coin cell however when I switch to USB to power it (battery removed, of course), there's a bit of noise in the 200Hz to 10KHz ...
0
votes
1answer
16 views

Can I use an Adafruit Trinket as a simple Android peripheral?

I want to control the standby state of an LCD panel through an android media PC. I'm thinking of using a Trinket as a cheap android USB peripheral. Is this possible? Or should I be looking at an FTDI ...
2
votes
0answers
45 views

USB termination on STM32F437xx

I'm about to layout the USB connection on our boards and wondering whether the termination resistors and pull-up on D+ are necessary when using the STM32F437xx. The datasheet tells: ...
0
votes
1answer
62 views

My take on an automatic source selector between USB and wall supply

This is my take on an automatic source selector between USB and a 12Vdc wall supply. There is something similiar in this post. The problem I have is the Voltage drop across the diode on the USB 5V. ...
0
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0answers
30 views

USB analyzer with trigger generation

We're trying to track down a really nasty problem. We have a microcontroller with an embedded USB device controller engine. Every once in a while, the device NAKs an incoming endpoint 0 Set_Report ...
0
votes
1answer
41 views

How to get USART and USB-Serial working on the STM32F4Discovery Board?

I'm programming a STM32F407VG chip on the STM32F4Discovery board using CooCox CoIDE. I've stitched together a program based on some examples and tutorials I found online to get USART1 through pins ...
0
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0answers
29 views

AC to DC converter for 5V USB Charger [duplicate]

I have been looking around to understand how phone chargers can pump out 1-2 Amps of current through the USB port in such a small package. I am sure they do use a transformer for isolation. One of ...
0
votes
0answers
40 views

Custom USB 7 port hub PCB dasiy-chain

I had a schematic laid out for a custom USB 2.0 7-port hub I needed to create for a project of mine. It currently uses Ethernet RJ45 sockets to provide power and data to each hub (2 Ethernet ports for ...
3
votes
1answer
109 views

Floating supply and USB ground

I have a somewhat complex circuit controlled by an Arduino, which is supplied by a self powered USB hub (earth grounded 5V supply). A part of the circuit has to be powered by 12-20V DC. When I plug ...
0
votes
2answers
61 views

FTDI cables confusion

I went to the store and asked for a FTDI cable however, I need a bit of assistance, apparently I didn't properly do my homework before shopping and I ended up with upper pic. I need an FTDI cable to ...
2
votes
1answer
59 views

STM32 USB: detecting connection and disconnection

Using STM32F4 USB Mass Storage Controller example in Device Mode, how do you detect connections and disconnections with a host controller? I tried polling the VBUS pin state yet it could be high from ...
0
votes
0answers
10 views

DIN 5 keyboard to USB? [migrated]

I have an old keyboard with a DIN 5 connector, I noticed that the wiring on a DIN 5 connector is basically identical to the USB based 4 contact wiring. Can I just blindly wire a DIN 5 ( starting from ...
1
vote
0answers
40 views

SPDIF digital audio to I2S to USB controller

I'm looking to take a digital S/PDIF audio signal, decode it as necessary, and send it to a USB controller chip configured as a USB Audio Class device so I have plug-and-play with standard OS-provided ...
0
votes
0answers
21 views

Piranha LED board connected to USB charger [duplicate]

Can I use this Piranha Light board to connect to a 5v power source like a USB charger? Do I need something extra (more than an USB-cable)? And can I connect more boards to the same circuit? (New to ...
11
votes
6answers
2k views

Is it possible to step-up the output of a laptop USB port to 12 watts?

I've got a USB device that requires 12 watts to charge. My laptop appears to output less that that. My question is: Is it possible to step-up the output of a laptop USB port to 12 watts?
0
votes
1answer
51 views

Drain Li-Ion battery by connecting USB +5V and GND

I have a sportswatch which can be connected to a PC via USB for downloading the training information, upgrading the firmware, etc. I have used those features for a year on weekly basis, but since ...
0
votes
1answer
30 views

USB OTG: Possible to perform emulation of slave device on master with drivers recognized?

I'm not exactly sure if this should be under a separate StackExchange topic altogether (programming maybe?), if it is, please move it and sorry for the inconvenience. I'm planning to build a device ...
0
votes
1answer
54 views

Digital Multimeter to RS232 Serial Port or USB - DT830D

I am new to Electronics and doing a hobby project. I want to take some readings and get them on the computer/laptop. I am ok with both RS232 (Serial) or USB (preferred). I have a DT830D Multimeter. I ...
0
votes
2answers
65 views

Can you turn a non-USB audio mixer into a USB mixer?

Ok. Pretty sure this sort of thing isn't possible but hey ho, I have a Behringer Eurorack UB1202 multi-channel mixer. I'm just curious if there is any way way to turn it into a USB ...
0
votes
0answers
18 views

Can I measure provided current/power by measuring voltage over resistor? [migrated]

Background I'm trying to get my scanner (CanoScan LIDE 100, USB 2.0, back says power input 5V/500mA) working with a Raspberry Pi. Whenever I issue a scan command it usually gives me a device I/O ...
0
votes
1answer
35 views

Apple iPod 30pin to micro usb

Not sure if this is off topic. I have an old ipod dock with a 30 pin male connect and I want to switch it out to a male micro usb. So that I can use the dock. I don't want to use an adapter as I want ...
0
votes
2answers
75 views

PIC USB host and device

I have been designing PIC based systems for several years, but this will be the first time that I am involved in a project based on USB communication. I don't exactly know where to start but I have ...
2
votes
1answer
108 views

How does a USB 2.0 Wall Charger negotiate current output?

I'm trying to use a mobile phone charger for my projects, and want a high current output. I have read this, however my measurements show something else. Here is a link to the Battery Charging ...
3
votes
1answer
93 views

Android Microchip Accessory Development Starter kit PIC24F

I have the PIC24F Android Accessory Development Starter Kit from Microchip. I am running Android 4.4.2 on a Samsung Galaxy S4, however I am unable to get the phone to recognize the USB device when ...
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votes
1answer
60 views

USB Serial Communication for STM32F401C-Discovery using Keil uVision5

I have developed a STM32f401c-disco board using Keil, and next I would want to be able to send data out (say just a "hello" string) via the serial link USB-ed back to my PC and show it (I have ...
2
votes
0answers
56 views

STM32F103: not working USB when I turn on the timer

In my project the USB works, if do not use the timer 2. As soon as I enable the timer, the USB is not defined on the computer with an error -71. I use libopencm3; debian; gcc arm; what is the ...
0
votes
1answer
56 views

USB 2.0 vs USB 2.0 OTG

I am looking for some microcontrollers with USB capabilities and some are said to have USB 2.0 HS Host/Device with PHY others say ...
0
votes
1answer
51 views

UL listing for USB device with battery, detachable cord and transformer

I want to import a device (for resale) that comprises the following components: Wall transformer (already UL listed), USB wire, LED light assembly, rechargeable battery (already listed). The ...
1
vote
4answers
344 views

USB PC Current Limit

USB2.0 specification says a device can draw 500mA. In my new design, I like to build it such that with correct adapter the device can draw 1A. My concern is with equipment out there. I cannot build a ...
1
vote
1answer
95 views

Connecting two USB DP/DM

I use Stm32 and recently upgrading my design. Current product uses built in USB full speed and I do everything via this port. (Fw upgrade, service, other usual use cases). In the new design ...
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votes
1answer
71 views

What does those symbols on these wires mean? (USB)

I got this cable while fixing my Microphone (Audio Technica ATR2500-USB). It came from a USB B type connector at the bottom of the mic. Does anyone know what does these symbols on the wire correspond ...
0
votes
1answer
63 views

Power supply for usb devices

I had a question that I was hoping someone could help with. I am building a cluster of raspberry pis to do research on and I decided the best way to power all the nodes was through micro usbs. (I ...
1
vote
1answer
157 views

How to use k150 pic programmer on Linux?

I'm trying to start with PIC microcontrollers. I bought this programmer: http://www.kitsrus.com/pdf/k150v2.pdf and a 16F628A. But I'm not able to use it with my Arch Linux... How can I do that? Thx ...
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votes
1answer
62 views

LEDs and buttons - ready made [closed]

We want our first semester students to learn programming and see the results of their exercises on a LED matrix. Unfortunately, we can not start soldering with the guys in the first week, so we are ...
1
vote
2answers
85 views

Can I reasonably expect a USB connection manage a 3.7 Volt 6-8 Watt output at 1.9 Amps or less?

I am thinking about making a 510 Vape eCig mod that runs directly from USB. The cart I would like to attach to the 510 head has a 1.8 ohm resistance atomiser in it and wants to see under 2Amps (or it ...