Input 100-120V-50/60Hz, 0.5A
Output 5V-3A/9V-2A/12V-1.5A
Input 200-240V, 50/60Hz, 0.7A
Output 5V-3A/9V-3A/12V-2.25A/20V-1.35A/11V-3A (Max)
I know what V, A, W are and that my charger is a 33W charger. How did they come to these conclusions? Please help
In: 1
The profiles listed on the output lines are supported fast charging voltage/current profiles (presumably USB-c power delivery with those numbers)
>11V-3A
That is how you get 33 watts of output. Its is 11 Volts X 3 amps.
All those input number are the power draws at a given voltage. At 100-120V-50/60Hz, 0.5A but at 200-240V, 50/60Hz, 0.7A.
So it will draw more power at 240V than at 120V.
USB (USB-C PD) chargers support a number of typical voltages, 5V, 9V, 12V(?), 20V. At each voltage they support a maximum current, typically 3A. The phone or other consumer picks what suits them.
This is how you get the watt rating. 5V×3A=15W. If your phone only accepts 5V, the max is 15W, because higher currents aren’t safe for cable.
The manufacture supports the standard volt + ampere combinations for maximum compatibility, up to the max power they can deliver.
Your charger is a bit weird with the 11V line, not standard and not common. All others are typical, capped at 33W.
You tagged this as physics, but there’s no scientific explanation. They are following an industry standard (partly), an arbitrary convention.
They don’t come to those conclusions, they use circuitry that specifically turns the charger off if the voltage does not fall into one of the INPUT brackets. For the output they also use circuitry that makes the charger output exactly one of those brackets (it’s up to the USB device to negotiate with the charger which mode they want to operate in)
It’s physically designed to provide those standard output combinations.
Watts = Volts × Amps. So the four charging modes it supports give you 15W, 18W, 27W, or 33W.
The input numbers just mean that it is designed to draw 0.5 Amps if connected to 100V to 120V, e.g. in North America. AC power is a sine wave so you’ll sometimes see it rated as 110, 115, or 120 V depending on how they measure it.
120V × 0.5A = 60W … so basically it is sucking up to 60W of the wall power and outputting up to 33W to the phone.
In Europe they use double the voltage on normal circuits, and in that case it draws 0.7 Amps. 240V × 0.7A = 168W … seems like overkill but that’s how they like it there; it helps keep the room nice and warm in the winter.
The 50/60 Hz just means it supports 50 Hz or 60 Hz (how fast the AC power switches directions); Europe uses 50 Hz, North America uses 60.
Chargers used to be very simple. They only took a single type of input (provided by your local power company) and only gave a single output. The company that makes the charger crates a circuit to transform the output of the power plant into the input of your phone is expecting.
As technology got better, they figured out how to take different power plant outputs (depending on your country) into different outputs for different devices. You phone now communicates with your charger to decide what’s the optimal output depending on the battery level (that’s why there multiple outputs).
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