Linked Questions

23
votes
4answers
5k views

USB Shield. To ground or not to ground?

I have been given a device at work to do some testing on. Basically an IC is becoming obsolete so I need to test a replacement part. Upon redoing the ESD checks, the device failed. I checked the ...
6
votes
5answers
5k views

USB micro B receptacle has 6 mounting tabs. How many do I actually need to ground?

This USB micro B has 6 mounting tabs. If I ground none or only 1 of them, will it ruin the signal? There is a pad for the signal ground that is separate from the mounting tabs. Fyi USB 2.0 has a max ...
8
votes
1answer
2k views

Proper shielding techniques for chassis grounded equipment located 30 feet apart

I am just hoping to get some best practices out of this discussion: I have two pieces of equipment that are located about 30 feet apart and bolted to a metal frame (chassis ground). They interface ...
2
votes
1answer
1k views

Connecting the Shield of a strain gage cable connector to PCB with ADC

I have a half-bridge strain gage sensor (pre-assembled product) with a 30cm cable, which I am trying to interface with my PCB containing a 24-bit ADC. The connector at the cable end toward the ADC (i....
4
votes
2answers
1k views

Where to connect shield and ferrites in PCB with isolated planes

I have a device which has two sections of the PCB completely isolated form each other, but connected by an isolator IC (PN: ????). I think I need to shield the whole device for reducing EMI because ...
2
votes
1answer
776 views

How do I deal with multiple, separate shields?

With HDMI or USB3.0/3.1, a cable assembly, in addition to the main braided shield, has multiple separate shields for each differential pair, here an example of a USB3.0 cable: Image source The inner ...
1
vote
1answer
379 views

Why is the usb shield always tied to ground (GND pin)?

The shielding on a cable is to avoid interference from the outside world however it is always tied directly to the GND pin. Not inside the cable itself but inside a device. Every single device I take ...
3
votes
1answer
340 views

Power selection circuit for USB or DC Jack - both at 5V

I am designing a new board, where I need to detect if the DC input jack for powering the board has been plugged and then disconnect the USB power supply. I also need to detect it with the uC in order ...
1
vote
1answer
168 views

USB shield for analog and digital ground?

I'm new to Mixed-signal design and I'm having trouble deciding how to connect my digital and analog ground. I'm doing a 4 layer design, so I have a split ground plane. As I understand, since I'm ...
1
vote
1answer
112 views

Is it a good idea to connect the mounting connectors of a USB port?

I have designed multiple small PCBs for personal projects, and have used USB ports many times for an output. I have always wondered if it is a good idea to connect the two mounting holes for the USB ...
1
vote
1answer
136 views

How to shield a battery powered instrumentation with USB interface?

I would like to ask for advice on shielding the following setup. I have a measurement target sitting inside a Faraday cage, connected through a shielded cable to a measurement circuit. The cable ...
2
votes
1answer
80 views

Atmega32u - Ground in bus powered configuration

The Datasheet provies an example configuration for when the device is powered from the bus, and shows the bus Vss connected to ...
1
vote
1answer
113 views

Where to connect shield in USB power supply for Arduino?

I'm making a 5 volt portable regulated power supply (using LM7805 regulator IC) for Arduino UNO. I'm planning to use a USB connector as its output socket, this way I can just plug and power the ...