Lasersaber strikes again. A joule thief king ?

[conradelektro]

Has any one tried the Touchstone TS3002 chip with their demo board yet?  This has an amp draw of less than 1 micro amp.  I happen to have one of these demo boards and will dig it out and see what happens.  I also have about 6 spare chips for it.

This should be able to drive an led for a very, very long time.

Bill

The TS3002 is difficult to get and very difficult to handle (so small). If one reads the data sheet it becomes clear that in any useful application its power draw is a few µA (4 µA, not only 1 µA).

One would need a breakout board like this: http://uk.rs-online.com/web/p/clock-timer-development-kits/7877201/ (very expensive)

I think that the TLV2401 (used as an astable multivibrator, http://at.mouser.com/Search/Refine.aspx?Keyword=TLV2401IPE4) is best, also because it is available in a practical TIP T8 package.

With the TS3002 or the TLV2401 one needs an additional transistor to drive a coil (back EMF drives LED). With the TS3002 one could get away with only one battery, which would be nice. May be there will be a cheaper TS3002 breakout board available or a 1 Volt OpAmp.

It is not easy to work at 1 µA and 1 Volt. That is the reason why LaserSaber uses the 9 V power source (9 times more Wattage, 9 V and 1 µA --> 9 µW, 1 V and 1 µA --> 1 µW).

If one uses any integrated component, it is hard to beat what I did at (with very careful design one could maybe get at half the power draw, 15µW to 20µW)
http://www.overunity.com/14591/lasesaber-strikes-again-a-joule-thief-king/msg402574/#msg402574
http://www.overunity.com/14591/lasesaber-strikes-again-a-joule-thief-king/msg402695/#msg402695

Greetings, Conrad

P.S.: I do not want to diminish LaserSabers great work, I juts look at the numbers. A big advantage of his approach are the few components, the drawback is the special coil and the difficult transistor choice. But at 1µA any component is a difficult choice, even today.

[d3x0r]

replication of laser saber's latest...

http://www.overunity.com/14524/3v-ou-flashlight/msg402895/#msg402895


mpsa16 isn't so unusual of a transistor...

[conradelektro]

replication of laser saber's latest...

http://www.overunity.com/14524/3v-ou-flashlight/msg402895/#msg402895


mpsa16 isn't so unusual of a transistor...

Interesting.

Using a modern integrated component is of course the bland and boring thing, no hope for OU. But it would be transparent and easy to replicate. I just wanted to see how well the MAX931 circuit compares and if I could make it work at all (if the concept was right).

Naturally, the more interesting and exciting thing is what LaserSaber (and his bona fide replicators) are doing. One can even hope to suck electrons from somewhere (ground, static electricity in the air, ...).

Getting the MPSA16 (or NTE47) from standard channels is not possible, you have to go to sellers who specialise in outdated componets and how long will that work? But I think one can find a modern equivalent given the expertise and determination. I guesse one can work with a small cap at the base of the transistor to make the pulse shorter.

Greetings, Conrad

[d3x0r]

Interesting.

Using a modern integrated component is of course the bland and boring thing, no hope for OU. But it would be transparent and easy to replicate. I just wanted to see how well the MAX931 circuit compares and if I could make it work at all (if the concept was right).

Naturally, the more interesting and exciting thing is what LaserSaber (and his bona fide replicators) are doing. One can even hope to suck electrons from somewhere (ground, static electricity in the air, ...).

Getting the MPSA16 (or NTE47) from standard channels is not possible, you have to go to sellers who specialise in outdated componets and how long will that work? But I think one can find a modern equivalent given the expertise and determination. I guesse one can work with a small cap at the base of the transistor to make the pulse shorter.

Greetings, Conrad

I ran down to frys and picked up some NTE47's...
radio shack has them...


oops it's MPSA18 ; jameco...


not so esoteric...

[TinselKoala]

I'm afraid I don't trust these tiny current readings done by conventional DMMs, in circuits involving capacitors and pulsing outputs.

Here's an idea I'm experimenting with: calculate the average current by monitoring the voltage drop on the capacitor over a known time interval.

That is.... you have your reservoir cap, in my case the 10F supercap in the TKBloomer circuit. You charge it to a precise known voltage, say 2.000 volts, and with _no load_ you see what its voltage is after 10 minutes. Say it's 1.998 V. Now you can compute the open-circuit leakage current of the capacitor, from knowing the change in voltage, the capacitance, and the time interval. Now recharge to 2.000 volts and turn on the load. After 10 minutes, look at the voltage on the capacitor. Say it's 1.500 volts. Now you can compute the _total average current_ delivered by the cap over the ten minutes, and subtract the leakage current determined earlier, and you will have the average current drawn by the load during your time interval.

I think this process may be more reliable than using the DMMs to measure microAmp currents.

ETA: On the other hand, since the electrolytic caps have the "recharge" phenomenon, as I've illustrated in the TKBloomer video ... they can even light the LEDs when their voltage is _rising_, so maybe using the voltage on the cap isn't such a viable idea after all. I'll have to run some tests....