jamesnguyen
Electrical
- Sep 6, 2010
- 49
Hi,
My company makes a portable device (battery operated). If we connect the device's USB port to a PC while it sits on the charger, sometimes device resets, sometimes the PC reset, sometimes both reset.
I think the problem is caused by the voltage differential between the grounds of the two systems. As the charger is powered by a linear, 2-prong AC/DC adapter (transformer-based), its "ground" is actually floating with respect to the PC's USB ground. I got hundred of volts between the two grounds of the two systems! I think when the two system connects through USB, the voltage difference causes a large current transient, which causes the two systems to reset.
Is there a way around this?
James
My company makes a portable device (battery operated). If we connect the device's USB port to a PC while it sits on the charger, sometimes device resets, sometimes the PC reset, sometimes both reset.
I think the problem is caused by the voltage differential between the grounds of the two systems. As the charger is powered by a linear, 2-prong AC/DC adapter (transformer-based), its "ground" is actually floating with respect to the PC's USB ground. I got hundred of volts between the two grounds of the two systems! I think when the two system connects through USB, the voltage difference causes a large current transient, which causes the two systems to reset.
Is there a way around this?
James