# Need to take 5v 1a step up to 12v 2a with only using the 5v power supply. Is this possible at all?

#### bytemedj

Joined Aug 13, 2015
4
I am trying to take a 5v 1a current input and get an output of 12v 2a. Ive seen all kinds of step up modules mut amperage depletes. I want to boost the amperage along with the voltage. Is this possible and if so, how? I am very new to this so please dumb your answers down for me.

I want to thank you ahead of time for taking your time to deal with an amateur for any assistance needed. Any help is greatly appreciated!

#### paulktreg

Joined Jun 2, 2008
799
You want 24W (12V x 2A) from a 5W (5V x 1A) source. Can't be done.

The maximum you could get at 12V would be approx 300~400mA.

#### JWHassler

Joined Sep 25, 2013
284
The 5v/1Amp supply is capable of delivering 5x1=5 watts of power.
At 12V it would still deliver 5watts (less inefficiencies) for a current capability of 5/12 amps.
It's physics.

#### bytemedj

Joined Aug 13, 2015
4
Thanks for the info, you guys are great! Youve saved me so much time.

If I have a battery that puts out 5v2a power and I split that will that drop down to 5v1a per line? Im assuming when you split it you keep voltage but lose amperage. Can I also assume that whatever device is running off that power the amperage will drop only by what amperage is required to run the unit? So even if I run 3 items off of it and they drain under 2a, im fine, right?

Thanks again, im sure ill have more questions later.

#### Alec_t

Joined Sep 17, 2013
12,000
Provided the 3 devices are each rated for 5V and their total current draw is no more than 2A then fine. But what battery do you have that is 5V?

#### dl324

Joined Mar 30, 2015
12,790
I am trying to take a 5v 1a current input and get an output of 12v 2a. Ive seen all kinds of step up modules mut amperage depletes. I want to boost the amperage along with the voltage. Is this possible and if so, how? I am very new to this so please dumb your answers down for me.
Your power supply will supply 5W (P = IV = 1A * 5V = 5W).

Step-up regulators can generate higher voltages, but they are never 100% efficient. At 100% efficiency, you would get 420mA (I = P/V = 5W/12V = 0.42A).

Typical step-up regulator efficiency is 65-95%. Assuming something in the middle, you could get 0.8 * 420mA = 330mA

#### dl324

Joined Mar 30, 2015
12,790
If I have a battery that puts out 5v2a power and I split that will that drop down to 5v1a per line?
Not necessarily. Each device is a load on the battery and each will try to get the current it requires.

Batteries are rated in AH (Amp Hours). A 5V 2AH battery would provide about 2 Amps for an hour, 1A for 2 hours, 0.5A for 4 hours, etc (ignoring any self leakage and any other parasitics).
Im assuming when you split it you keep voltage but lose amperage.
You lose neither voltage or current.
Can I also assume that whatever device is running off that power the amperage will drop only by what amperage is required to run the unit? So even if I run 3 items off of it and they drain under 2a, im fine, right?
Each device will attempt to draw what it requires. As long as that's less than what the battery is rated for you're good to go.

You can often draw more current from a battery for short periods. A 2AH battery might be able to provide 4A for half an hour...

#### bytemedj

Joined Aug 13, 2015
4
Thanks for all of the great information everyone!