# adjustable voltage source with 10A current

#### ilginsarican

Joined Jul 13, 2017
109
Hello,
I need adjustable voltage source that can be regulator ect.
But the point is that my load will draw current(About 10Amp) suddenly(100 ms), but the voltage will not drop suddenly.
I've tried LM2576 but output voltage has dropped.

#### BobTPH

Joined Jun 5, 2013
2,731
You either need a supply that can handle 10A or a capacitor to provide the short busrt of current.

Depending on the drop you can stand, the capacitor will likely be a supercap. I did a quick calculation and, for a drop of 100mV, a 1F cap is required.

You can get boards that have supercaps along with circuitry to control the charge and discharge currents quite cheaply.

Bob

#### AlbertHall

Joined Jun 4, 2014
10,776
There is no supply when suddenly the load changes from zero to 10A will maintain the output voltage absolutely unchanged. You need to be clear how much drop and for how long is acceptable.

#### ilginsarican

Joined Jul 13, 2017
109
You either need a supply that can handle 10A or a capacitor to provide the short busrt of current.

Depending on the drop you can stand, the capacitor will likely be a supercap. I did a quick calculation and, for a drop of 100mV, a 1F cap is required.

You can get boards that have supercaps along with circuitry to control the charge and discharge currents quite cheaply.

Bob
Supercap is a good idea.
I will use 10 supercap in series and first voltage stage will be 2.7V,second will be 5,4V and up to 27V.
In this way the voltage will be adjustible.Maybe I use mosfet to control voltage stage.
Rated current of the supercap is about 40A,it is enough for me.

#### BobTPH

Joined Jun 5, 2013
2,731
Be careful. You need cirrent limiting and balancing if you try to roll your own. You can get boards that do all of that, though the ones I have seem top put at anout 15V.

Bob

#### AnalogKid

Joined Aug 1, 2013
8,806
Your question is missing some important information.

What is the output voltage adjustment range?

What is the average output current before it jumps up to 10 A?

What is the maximum acceptable output voltage change when the 10 A load transient appears?

ak