Hi All my friends (specifically from the "Wattage in voltage devider"), I have successfully build A switching PSU that briings my 12VDC wall wart down to anything, now for the same educational purposes, I wanna build a PSU that increase the voltage from the wall wart to, well anything. Task is it's own application. Now this guy: http://www.instructables.com/id/Simplest-Ever-DC-DC-Boost-12v-to-73v/?ALLSTEPS makes a DC to DC Booster, but only for 78V, I want to be able to adjust the voltage to say any value between 12 and 30V and if possible have my voltage regulator (http://forum.allaboutcircuits.com/threads/wattage-in-voltage-devider.103490/page-17 ISB123, you're the MAN!) that brings down the voltage, also operate upwards on the same circuit. Is this doable?

All Google designs require ICs that I can't obtain :-(

I can get LTC3401! but it's surface mount, dunno how to do that with vero board

 

Watch this:

 

cool video, can't get LT1370 only surface mount LTC3401, which I don't know how to do with veroboards. So unless there's another way that doesn't require large heatsinks I can't build this, or can I?

 

You are going to need heatsink anyway since you are inputting low voltage\high current to get high voltage\low current.

 

You can mount low power SMD components on Veroboard using the 'dead bug' method, i.e glue the IC upside down on the board and run wires from the copper tracks to its legs. That clearly won't work though for ICs that need a heatsink/ large copper area to dissipate heat.

 

isn;t there something we can build with the tip122 and bc337 like in http://www.instructables.com/id/Simplest-Ever-DC-DC-Boost-12v-to-73v/?ALLSTEPS

I can obtain a tip122 and bc337

 

cool video, can't get LT1370 only surface mount LTC3401, which I don't know how to do with veroboards. So unless there's another way that doesn't require large heatsinks I can't build this, or can I?

You can solder it on SMD adapter however MSOP isnt easy for beginners, its impossible if you dont know how to do it.

 

the chip isn't going to work, but somebody http://www.instructables.com/id/Simplest-Ever-DC-DC-Boost-12v-to-73v/?ALLSTEPS built a 12v-73v booster using tip122 and bc337 and some capacitors and a incuctor. and one resistor. Can't we derive something from his circuit because 73V is too high

 

that's just a joule thief kind circuit, nothing special and not particulary good.

how much current do you need at the output? then I can advice you what's best.
You can boost with the MC34063, the TL494, with a NE555, and many other ICs.

Its even possible with the LM317 (but gives audible noise and clickering on load/ voltage changes)

You need feedback obviously.

 

I can get the MC34063, which is a switching regular in an 8 pin DIP package, shouldn't have heat problems
I can get the TL494, which is a switching regular in an 16 pin DIP package, shouldn't have heat problems
And I can get the 555
I think I'd like to use the MC34063, looks easier to hook up; can anyone help me design its variable step up circuit.

looking at the datasheet (of the MC34063), the normal step up delivers 175mA, but there's a npn configuration that produces 1.5A
http://www.mantech.co.za/datasheets/products/MC34063.pdf

I'm learning here any advice would be appreciated

I already have a stepdown with maximum of 37V input, although its expensive, shouldn't it be easier to buy a good toroidal transformer: Toroidal Transformer, 160VA 0-35/0-35 what would that give me as volts output? (and current) 35V, 4.5A?

please see http://forum.allaboutcircuits.com/threads/transformer-help.104352/ I think its an easier avenue for my goal

 

So how much current do you need? Bear in mind that high current inductors may be more difficult to source and/or more expensive.

 

I don't know how much current I need, I'm still learning, and haven't had much experience designing or building