Search results

yeah. thats about right :P it is a bit hard to explain you want to make spikes with the inductor, so that you can get more voltage, thats why its called a step up converter.

thats true, i should have changed the output voltage label

the inductor produces high voltage spikes, and the capacitor smooths all the spikes out to get DC

inductors step up voltage using the 'flyback' property, when you charge an inductor and then disconnect the current, the magnetic field in the coil collapses and the change in magnetic flux produces a high voltage spike. if you have ever had one of those trick shocking pens, they have an...

you don't actually have to be 'grounded' to ground yourself. if you just touch the bare metal legs of your table, that will get rid of all the static in you. or you could just not touch lasers after walking around on carpet in your rubber shoes :P it really isn't a good idea to be plugging...

the only reason you would want the amp is so you can connect the ground of the LD to ground. otherwise you can't have the two contacting each other, this makes it hard to heatsink lasers when you have it mounted in a metal flashlight body, where the body is connected to the battery an inductor...

I was going to try the LT6106 but the ZXCT1009 looks good.

the max8625 doesn't have an adjustable current limit, it is set at 2A "The MAX8625A features current-limit circuitry that shuts down the IC in the event of an output overload." and the lm3578 is only buck or boost, depending on how you set up the inductor. i am sure the right chip must be out...

YES! if a higher voltage is input, regulation will go out the window, and the diode will probably blow. it is a good find, maybe not for reds, but for bluerays. the only better find would be one of these with boost/buck capabilities

oh yeah. just read the rest of the datasheet... so it is a constant current regulator, as well as a voltage reg if its step up only, you will need to make sure the input voltage is lower than the LD voltage. in this case it will regulate the current or the voltage, whichever one is higher. so...

well you could, but the feedback voltage is quite high (1.2V) so 1.2V would be wasted in the sense resistor, it just leads to less efficiency. you could hook it up like the third diagram above, using an amplifier to amplify the feedback voltage. you could use any adjustable switching chip like...

and that chip you mentioned is constant voltage. it only has a MAX current of 800mA maybe this will help explain how a CC smps works (its basically the same as the lm317)

yeah your dad is right. its been done here http://www.laserpointerforums.com/forums/YaBB.pl?num=1212653254/60#63 here http://www.laserpointerforums.com/forums/YaBB.pl?num=1209911140 and here (this one was the thread that sparked all the ideas, has heaps of info)...

because i haven't gotten around to it yet. i am in the middle of uni exams, which will be over tomorrow

his is just like this design but it has a high side current sense amplifier, the 2nd chip on the board. this makes it easy to adjust current with a pot and leads to slightly higher efficiency (because of less loss in the current sense resistor) it also allows the diode to be connected to ground...

yes there is. the tps61200 has a feedback reference of 0.5V, the 61202 has a feedback reference of 5V the 61201 and 2 are supposed to be pre set constant voltage regulators, the 61200 is the adjustable version basically you can't use the 01 and 02 versions for constant current. so in your...

i posted it in that other thread, but here it is again. the question is, do you understand how it regulates the current? the voltage across the resistor will equal the current times the resistance. and because the feedback reference voltage is 0.5V, the driver will apply more voltage (and thus...

its only a blueray :P i don't think heat dissipation is that big a deal. main reason i chose it over a section of copper pipe is that it isn't conductive (i can't have the - of the battery touching the body of the laser with my driver) as far as connecting contacts and stuff, hot glue is my...

and here is toked's board resized ::)

you mean tps61200 right? the tps61201 is pre set at 3.3V which one did you trace? mine or toked's here is the schematic for mine