How to make 76V from 38V
How to make 76V from 38V
(OP)
Hi, this is probably a simple question but i need a supply voltage of 70+ V. The "start voltage" is a battery with 9V. I am currently using MC34063 from ST electronics (dc-dc step-up converter). This circuit delivers 38V output.
How can i step up the voltage further? Can I invert the 38+ (to 38+/-) or is there any other solution for this problem?
Grateful for all answers, mr_embedded.
How can i step up the voltage further? Can I invert the 38+ (to 38+/-) or is there any other solution for this problem?
Grateful for all answers, mr_embedded.





RE: How to make 76V from 38V
If you use a different type of switch mode supply (e.g. a forward converter) this has a transformer to isolate input from output, so you can specify the input to output turns ratio of the transformer to get the higher 76V output that you need.
RE: How to make 76V from 38V
If that's a typical 9-volt alkaline battery (~0.5 A-hr), then you'll need to be very careful with efficiency. It'd be easy to come up with a DC-DC step-up 'solution' that would drain the battery in minutes.
RE: How to make 76V from 38V
RE: How to make 76V from 38V
RE: How to make 76V from 38V
Grateful for your help,
MrEmbedded
RE: How to make 76V from 38V
RE: How to make 76V from 38V
RE: How to make 76V from 38V
Search Google Images for the following search terms:
1) DC-DC converter circuits
2) Voltage multiplier
Google Images is nice because you can scan the circuits right on the results page.
Option 1 should find you a suitable chip with reference design.
Option 2 would be combined with an oscillator of your own design.
Option 1 would be better.
RE: How to make 76V from 38V
RE: How to make 76V from 38V
Two batteries and two convertors in series. Advantage, double the run time before changing batteries.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: How to make 76V from 38V
Thanks so far!
mr_embedded
RE: How to make 76V from 38V
seems like MAX668 and a bunch of others would be good candidates. Unclear why this is dragging on so long.
TTFN
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RE: How to make 76V from 38V
RE: How to make 76V from 38V
http://www.youtube.com/watch?v=I2fD-hYVLxE
RE: How to make 76V from 38V
Here's a Nixie tube power supply that turns +9 to +12 volts into +170 at about the power level you're looking for. The control circuit is a common 555 timer. Just about any SMPS chip that uses an external diode and switch could do this.
Modifying it for +5 volts in and 76 volt out shouldn't be too difficult.
www.ledsales.com.au/kits/nixie_supply.pdf
RE: How to make 76V from 38V
RE: How to make 76V from 38V