The voltage on the charger is less than on the charged
Hello. On a rechargeable device, USB input, voltage 5V. And on the charging output 5.1V. Is such a discrepancy allowed in the voltage and what are the tolerances? And as I understand it, the current takes the device how much it takes?
This is a slight deviation. You measured the voltage without load, and when you connect a charged device there will be some voltage drop. There is a charge controller in the tablet, phone, etc., which provides the limitation of current and voltage at the required level, by adjusting these parameters during the charging of the device.