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dc power boost

dc power boost

dc power boost

(OP)
I have a dc source of about 1 volt and I am looking for a circuit to boost the voltage to 2 volts at 20 ma

RE: dc power boost

That will be very tough.  Can you use other power more than 1V from somewhere else to do the conversion on the 1V? Probably not. :(

RE: dc power boost

I have not done the calculations but to boost the DC source you could put it through an inverter to make it AC, step up the voltage with some type of AUxilary transformer, and use a rectifier on the transformer output to turn the power back to DC. To limit the current to a particular load, set up a current divider circuit. or size the transformer accordingly.

These are just some thoughts, I hope they help

RE: dc power boost

There are many devices that are powered from a single 1.5 volt 'AA' cell and make higher voltages (flash on disposable camera is just one example).

I'm not sure how low these circuits can go (PS voltage) but I think that some might be able to run as low as slightly less than 1 volt.

Where does the 1 volt come from? It's an odd voltage.

RE: dc power boost

it would be possible to make a DC to DC converter with
much lower input V, using synchronous vibrator ...

<nbucska@pcperipherals DOT com> subj: eng-tips
read FAQ240-1032

RE: dc power boost

You are talking mechanical?  That's an idea.

RE: dc power boost

Smoked: it is but an old one: around ww2 it was used with kerosene lamp/thermoelectric generator.

electromech. vibrator chops lowV for xformer. extra two
-- SPDT-- contacts ground one end of secondary. The  centertap is the DC output.

I suggest a better solution:

Use 3-4V rechargable battery to drive oscillator-FET swith.
FET chopps low V; start from battery, recharge it from AC output.

<nbucska@pcperipherals DOT com> subj: eng-tips
read FAQ240-1032

RE: dc power boost

Just for fun, I once built a flyback boost inverter to convert around 10mV to six volts. It used a SINGLE thermocouple junction and it worked, provided the drive electronics was externally powered.

The thermocouple was a pilot flame detector salvaged from an old gas hot water heater. The thermocouple generated around 10mV at 50mA (from memory) when attached to a soldering iron tip !

I did get my six volts, but even my multimeter loaded the output significantly. Flea power indeed, only half a milliwatt input power, but it was an interesting thing to try.

It is what happens during retirement, too much spare time.

RE: dc power boost

IrStuff has the answer.  Nice find IR!  I didn't even bother to check thinking 0.2V was too little head for the controller.
Sweet.

Thanks for that info nbucska!

Warpspeed.. external powered... uh huh.. with that sneaky balancing resistor in there between the external power and the thermopile??   What specific drugs were utilized? And were they used in the design process or the testing?

Yeah I bet it had horrible load regulation.  Flea complain?

RE: dc power boost

There were thermo electric power supplies built in the 50s and 60s that used thermo piles to generate power.  The out put votage was 1 or 2 volts.  The power source was a radio active isotope of some kind.  They were big 200 watts or so. The navy used them to power undersea listening devices or something.  There probably still out there somewhere.  
Westinghouse made the power supplies I saw. It was the same division that built sonars and polaris submarine systems.  I don't think it exist anymore.  

RE: dc power boost

While working on the Alyeska Pipeline I came across mysterious looking tank shaped things every now and then.  I asked about them.  Turned out the Alyeska guy I was working with serviced them.  They are thermoelectric generators made in Israel. They put out about 120W.  They all have large buried propane tanks that my associate drives around and fuels once a year.  They provide SCADA power.

RE: dc power boost

Thermopiles are pretty common.  The TOW missile has a thermopile for powering the guidance and tracking system.

TTFN



RE: dc power boost

Ah no kidding?!?! That is really, majorly, clever!  That was some serious outta the box thinking there.  Dump a bunch of batteries out of the payload. Very sweet.

RE: dc power boost

The main reason for that is that the thermal battery has no problems with storage life.  

As you might imagine, since TOW dates back to Vietnam and any other form of energy storage would bleed down over any normal military storage, a more permanent energy source was needed.  The thermal batteries, once the chemical stability is dealt with, can be stored for long periods, and then removed and immediately used.

TTFN



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