As near as I can figure USB outputs have following specs for power. I am not interested in data rates.
USB 2.0, 0.5A Voltage 5.0V+.25V -0.6 10Ω 2.5W
USB 3.0, 3.0A Voltage 5.0V+.25V -0.6 1.67Ω 15W
Over the years I have had several outputs that I questioned whether they were good or not in terms of voltage output. I'm thinking about building a tester based around the above specs. The resistors I show are to draw the maximum rated output for that port. I will be using this meter to give me a readout. I could not find any current specs for USB 1.0
USB 2.0, 0.5A Voltage 5.0V+.25V -0.6 10Ω 2.5W
USB 3.0, 3.0A Voltage 5.0V+.25V -0.6 1.67Ω 15W
Over the years I have had several outputs that I questioned whether they were good or not in terms of voltage output. I'm thinking about building a tester based around the above specs. The resistors I show are to draw the maximum rated output for that port. I will be using this meter to give me a readout. I could not find any current specs for USB 1.0
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