Contents
What is the voltage output of USB-C?
USB Power Delivery
| Version | Maximum Power | Voltage |
|---|---|---|
| USB 2.0 | 2.5 W | 5 V |
| USB 3.1 | 4.5 W | 5 V |
| USB BC 1.2 | 7.5 W | 5 V |
| USB Type-C 1.2 | 15 W | 5 V |
Do all USB-C cables have same voltage?
Passive Type-C cables support up to 3A by default at any USB-PD voltage range (standard voltages for fixed sources are 5V, 12V and 20V). So passive cables can carry up to 15W at 5V, 36W at 12V or 60W at 20V, if the source and sink negotiate an explicit contract for these voltage/current levels.
What is standard USB voltage?
Most computer USB ports supply 5V of electricity with a maximum current of 0.5A. This amount of current is standard across the majority of computers and means the overall power output will be 2.5 Watts at best. Later USB designs bring that current up to 0.9A.
How does USB power delivery work with voltage above 5V?
A USB-PD device uses that pin to negotiate the power profile determine if the cable is PD aware. Your ‘dumb’ devices don’t get damaged because USB-PD has a ‘start up profile’, by default it’s 5V/2A (in the 1.0 version):
What kind of power does a USB port provide?
The answer is simple: by default, a USB port initially provides the same safe 5V power, and nothing more. The higher voltages and capabilities of power providers are only available upon mutual negotiations between a device (consumer) and a port (provider).
What should the voltage be on a USB charger?
One charger might advertise 12V, while another might advertise 12.3V perhaps to compensate for voltage drop across the cable, while another might say 11.5V to indicate the voltage at the end of the cable under the full load. Most sources though will advertise some combination of 5V, 9V, 12V, 15V, or 20V when negotiating with the consumer.
Do you need a USB Type-C power adapter?
You will also need a USB Type-C power adapter that supports power delivery and a power delivery Type-C cable which has thicker power wires in the cable. This will minimize voltage drops across the cable and heat up less under high current loads.