DC-to-DC step up conversion..3v to 5v

[tr4il]

Is it possible to create a simple parallel circuit converting a 3v input (2 AA batteries) into a 5v output without an IC? Whats the simplest circuit diagram + components either way with integrated circuit or not..thanks a lot.

 

[dknguyen]

It's possible...but you'd basically be building an IC out of discrete transistors which makes it completely impractical. I think the simplest one you could do would still require a 555 timer and that has flip flops. FLip flops themselves are integrated circuits so you'd have to build each one out of a bunch of discrete transistors, as well as a voltage comparator (which is similar to an op-amp). THese are also ICs and require many transistors. I think it works out to be a total of about 20 to 45 transistors for the 555 timer, depending on the comparator you choose to make.

Why can't you use an IC? If you're just looking for a challenge, building a simple op-amp out of regular transistors is hard enough.

What do you mean parallel circuit anyways? THat does't make any sense.

 

[RadioRon]

What about something like this (attached)? Its a simple oscillator feeding a step-up transformer with an output rectifier.

 

[Ubergeek63]

why not just use something like a REG710?

 

[Hero999]

Because it's an IC and for some weird reason he doesn't want to use an IC

Here's an idea, it's pretty crude and will need some modifications but it will work.

https://www.electro-tech-online.com/attachments/switch-pdf.9974/

 

[Ubergeek63]

Because it's an IC and for some weird reason he doesn't want to use an IC

Perhaps, but it might be a misunderstanding on his part, that IC and a couple ceramic capacitors is all it takes to get a regulated 5V from 1.8V. So any 2 nickels or 1 lithium.

Dan

 

[RadioRon]

Its probably a school assignment or a challenge assigned by someone.

 

[audioguru]

He needs to ask his teacher how much current is needed at 5V and if the 5V needs to be regulated as his battery voltage runs down.

 

[tr4il]

sorry for the confusion. i would like to just do it the simplest way so IC it will be BUT im not sure how to calculate which actual chip to get based on its specs, etc. i ran across these **broken link removed** which suggests to use the **broken link removed**...to sum it up i'de prefer using the IC but don't know how specific those things get. thanks

 

[tr4il]

also: i need the constant 5v from the 2xAA batteries in order to power an optical joystick..

 

[Ubergeek63]

also: i need the constant 5v from the 2xAA batteries in order to power an optical joystick..

And for the minimal current required by an optical joystick and the additional requirement of a constant 5V, I will again recommend a REG710 since it will maintain 5V down to 2.5V in and stay in spec (logic levels call out 4.5-4.5V) down to about 2.3V.

 

[muszerjav]

I used MP1543. It's very simply, and cheap.
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