New answers tagged usb
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Powering Circuit via USB or 6VDC with Schottky Diodes
It seems to if the uC has power from USB then "Power"=0 in and "Power_En" out should go low.
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USB with only 2 green and 2 white cables
I'd suggest to use a multimeter and ring every wire individually versus the contacts at the connector. This way you will know with confidence to where it's connected and what's the intended function.
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How to figure out why (isolated) USB hub IC fails to be enumerated
I am afraid your USB2514B design has a serious deficiency. Pins 14 and 34 must be carefully bypassed by 0.1uF ceramic caps. Here is a snap from the manufacturer's application checklist:
Try to solder ...
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A proper way to stop power banks from turning off, and how to power low-current devices through USB
I had the same problem. Simple solution was to use a 100 ohm resistor in parallel to the 3.3V supply of the microcontroller. I also tried 330 ohm, but this was too high. I guess it checks if it is ...
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Type C and PD Adapter Detect and Negotation
No. As likely proven by the prototype.
There is no downsides unless you need them. And since you don't say what you are doing, it is unknown if you need them.
If you mean PD sources, none of the ...
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Custom ESP32-S3 board usb disconnect and reconnect every second
Your battery charger is pulling 1A without asking the PC if that's OK.
USB ports are not allowed to pull 1A.
The max current that can be negotiated is only 500mA.
And you can't pull 500mA without ...
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FTDI enumerates intermittently
Read table 3.1.1 or 3.2.1, depending on the package, in the datasheet. It tells you exactly how to connect power pins.
The 3V3OUT pin cannot be not-connected - in no power supply configuration it ...
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USB SuperSpeed Interface Connections
4.3 is how you connect two chips.
4.5 is how you connect a chip to a connector.
The reason is that transmit pins on all devices are AC coupled to cable, and receive pins on all deviced connect ...
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How to make an USB cable cross a door?
Unfortunately, essentially all consumer-grade smart locks are junk.
If this is your home, then you don't need a smart lock. They are much easier to open than a decent mechanical lock. Some of them ...
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Simplest way to design a PCB to mass program 10 ESP32's over a single high-speed USB-C port
You cannot connect more than one chip to USB. So you cannot put 10 CP2102 pins in parallel to one USB port.
You need a hub. Or rather, multiple hub ICs as likely you cannot find a 10-port USB hub IC.
...
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If I am forced to change the impedance of transmission line, how to continue?
The type-A plug-socket pair introduces a fairly big discontinuity. Whatever you're doing with those little traces won't matter much. Sure you'll get quantitative answers with a TDR - but they are not ...
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Charger IC cannot charge with Type-C Data+Charging Cable on USB Port
The USB A plug has 4 pins. +5V, ground, D+ and D-.
A USB data (upgrade) lead will connect all 4 pins. When charging, the D+ and D- are used by the device to tell the power supply what it needs. ...
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Arduino Nano Powering from Battery and USB Communication
For your specific question, if you power the device via 9V battery, and connect this to your (powered-on) laptop, it should work fine and not cause any problems to your laptop. The diode indeed ...
- 172k
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Are the 2 power sources connected inside this IC?
A multiplexer selects exactly one of the sources.
And even if both sources were enabled, the current limit and reverse current protection would prevent the large capacitor from having a noticeable ...
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Communication protocol for using 2 pairs of CAT 5 cable
Cat5 cable has four pairs; you can use two pairs for Ethernet,
or for POE (power over Ethernet) and network, and one pair for
video of the analog type (PAL or NTSC if it has to be in color).
USB isn'...
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Communication protocol for using 2 pairs of CAT 5 cable
RS-485 also does not convert to USB, and USB can't pass through more than 5 meters in any case, and CAT5 has incorrect impedance for USB.
Send the video as analog over one pair. Use second pair for ...
- 172k
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USB-C passthrough (including CC line) not making connection
To summarise and conclude:
It's not possible to create a USB-C pass-through device and remain compliant. To remain compliant, you would have to act as a hub.
The reason it's not possible is that USB-C ...
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Can I swap a USB power sources for a 3-AAA battery source?
If the string of lights is on one 2 conductor wire, they are wired IN SERIES if only one conductor is going into the bulb socket.
It would be unusual to be wired in parallel as that is more material ...
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High-speed Network Link between two Processors without Cable
There are versions of Ethernet that don't require traditional Ethernet cables at all. These incluse 1000BASE-KR and 10GBase-KX. Both are intended for communicating across a backplane between ...
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USB-C port as a power delivery and data transfer
Your device has 10k or 22k resistors to 5V. The role is fixed to be a DFP, which means it sources power and is a data host, and can't change role.
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Get Time-of-day from computer onto a USB connected connected device
Is there a standard way to retrieve Time-of-day from a "dongle" connected to a computer over USB?
Yes, there is. Sort of. In fact, there are two major ways that have relatively low "...
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Get Time-of-day from computer onto a USB connected connected device
Is there a standard way to retrieve Time-of-day from a "dongle" connected to a computer over USB?
Not that I'm aware of, and a quick scroll through USB device classes brings up nothing.
I ...
- 100k
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USB communication keeps disconnecting because of power dip/spike
I had similar issue, the desktop built-in USB port connection was failing when turning the spindle off (a Dremel via opto-isolated relay). I tried isolating as much as I could, no luck. I tried the C-...
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