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FrozenGate by Avery

Using a DC/DC converter to power the laser

no like if someone has an email company account they use that address and its free thats what i meant
 





toked323 said:
like what kind of project?
Click to expand...

Well, it depends on how many of these you want to build. If you want three drivers, you need 6 inductors.

PM me, and i will tell you what to say.


For the IC, it might be best, if you find someone you know offline, in your vicinity. You do realize, that these are so small, you might accidentaly inhale them? And that they have no legs? You're gonna have to be very patient and carefull. Everything else is easy, but the IC can ruin your day.

Might be best to order a spare one.
 
anyone know a place that sells lm3410's cheap i coil craft sent me my samples free of charger, that was easy
 
toked323 said:
hey someone want to order the lm3410 and ill pay you for it cause i dont want to pay 8$ for shipping
Click to expand...
Newark shipping (U.S.) would only be $5.20. (LM3410 price $2.98; different package)

DanQ
 
That one puts out a regulated voltage, and has very low current capabilities. Even less, than the MAX756. As soon as the current draw would increase, the voltage would drop rapidly.

It might be able to drive most blue ray readers through a resistor at 5V, or with adjustable voltage directly, but for higher powers, it would be useless.
 
Something to stir up your thoughts....
This thing has the LD cathode (-) at ground potential and allows the current to be adjusted within certain limits by means of a low power potentiometer. It operates from a 2.5 to 5.5-V source. However, do not expect it to pump 500mA in a future intergalactic blueray LD at 6V across it, as in any case the max switching current will not exceed the internally set limit of 2.8A (minimum of 2.1A). D2 and D3 are any small-signal schottky diodes. In some instances they can be omitted.
 

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the LM3410 portion is as per one of National's application examples of a sepic converter, found earlier in this thread. I designed the op amp portion. In its essence this isnt rediscovering America really. put in simple terms, im just sort of amplifying the drop across the shunt resistor /2x0.47 ohms/ by a variable factor.
I tested it, eventho i still dont have a complete PCB that accommodates all components. The LM3410 + inductors+filter caps have their own pcb and the op amp is literally wired to it.
 
I recognized the operation, you might be able to get away with using a single op amp on the shunt amp portion, and put the pot on the gain of the first amp. It's similar to the lavadrive2 in some ways, the reason I ask about testing it is that something I ran into with the added delay of the amplifier stage, the closed loop stability and output ripple should be verified under all of the possible operating conditions with an oscilloscope. But maybe this isn't an issue because the LM3410 may not has as high a bandwidth and closed loop gain as the chip I am using (more stable with a lower gain bandwidth).
Just an update on that: the design has been sent to the factory and completed drivers should be available in about a month.
 
MCP6022 has a GBWP of 10MHz, not all that fast, but i havent noticed ringing upon powerup. LM3410 has an internally delayed startup. In fact, there is a tiny spike /I will post pics on monday/, but a 10uF cap across the load smooths it out. At 260mA and 2.75V across the load, the rise time of the current is about 100us and there's no ringing whatsoever.
 
this is the voltage on a dummy load (3 x 1n4005 + 1x1n5817 /schottky/ ) at 400mA. The rise time is 87usec, ramps up smoothly; the voltage across the load is ~2.96V.
 

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hi i dont mean to butt in but i have a similar question and dont know where to turn to for answers :(

i need to step up 3v to atleast 7.5v+
i read the spec sheet for the LM3410 and it looks like it will output 7.5v+ from an input of 3v... but i dont know how to wire it up. any chance someone can provide a schematic for me please? pretty pretty please ;D

the input i have gives off 3v, i need a minimum of 7.5v out... anywhere between 7.5v and 12v output would be fine.
any help is GREATLY appreciated. thanks!
 
read the datasheet!
it has plenty of examples
to make it regulate voltage, just rig up a voltage divider between the output, feedback and gnd

the LM3410 is not the most practical of chips if you don't want to keep things really small.
there are plenty of through hole or SOT style chips that should be able to do the same thing
 
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