# Need help boosting voltage

#### jellytot

Joined May 20, 2014
72
OK, so I have a device that runs off 1 Watt / 12Volts. I want it to run off batteries, so currently I have 9 AA batteries in series powering it. But I want the device to be portable, to use 2 AAs and using [something] to boost the voltage to the required 12 Volts. Not sure if this is important, but the device is a micro-solenoid used intermittently, a fraction of a second on and 10 seconds off (and repeat).

Requirements: The solution of something should be compact, breadboard-able (DIP or through-hole package like TO-220) and easy to implement (I'm a electronics newbie).

Options I've discovered so far:
1) Get a DC-DC step-up switching regulator. I found 2 that may work, but they have 5 pins and I have no idea what to do with them.
2) Use a linear regulator like 7805 and use Zener Diodes to boost the output voltage.
3) Build a step-up convertor using inductors/capacitors/transistors. There are alot of examples out there but I don't know the math involved to get the desired output voltage from my input voltage.

I'm looking for a simple solution for my problem. Can anyone offer any advice?

#### crutschow

Joined Mar 14, 2008
26,994
A 12V boost switching regulator is what you want.

Just for your info, zener diodes don't boost voltage, they drop voltage.

How long is the solenoid on during each cycle and what battery life do you need?

#### Dodgydave

Joined Jun 22, 2012
9,936

#### alfacliff

Joined Dec 13, 2013
2,458
12 volt, 1 watt, running that much off a boost convertor and 2 double a batteries wont run very long. you will still need to get one watt out of 2 AA batteries, thats a bit much.

#### crutschow

Joined Mar 14, 2008
26,994
12 volt, 1 watt, running that much off a boost convertor and 2 double a batteries wont run very long. you will still need to get one watt out of 2 AA batteries, thats a bit much.
The OP stated it is a short duty-cycle, so it may be doable depending upon the exact value of the duty-cycle and a large capacitor across the batteries.