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#39224 Powerful Aquarium Lighting
Posted by
on 12 November 2012 - 11:29 PM
in
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#39235 Powerful Aquarium Lighting
Posted by
on 13 November 2012 - 02:24 AM
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#39127 Powerful Aquarium Lighting
Posted by
on 12 November 2012 - 05:42 AM
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Attached Files
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SteffNearlyFinished_fixedcutouts.zip 25.51KB
3 downloads
#38664 Powerful Aquarium Lighting
Posted by
on 07 November 2012 - 09:54 AM
in
General Discussion
pcb manufacturers
Or probably go with seeed.
Try editing the yellow pcb outline layer, I just looked at your board there is loads of room, but you may just have to reduce the copper pour a fraction.
Just fit (edit) the pcb edges to be 50mm apart. and move the copper pour to be at least say 1mm away. Move the fiducials too or you can just delete them.
Or when you are completely done with the other stuff I can do this step for you. I gave it a quick test it took just a few minutes.
the price from seeed is going to be $US 35.00 and if you waste $15 on something you dont want then you get free postage. The have a resistor book 805, but at $60 it is very expensive.
when you order from seeed you are not paying for service so do everything they say and it will be ok. I forgot my order number on one board but it didn't matter it still came. This time I put it under a big inductor so no-one could see it.
#37736 Powerful Aquarium Lighting
Posted by
on 21 October 2012 - 11:09 PM
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General Discussion
#40278 Powerful Aquarium Lighting
Posted by
on 27 November 2012 - 01:34 AM
in
General Discussion
This is actually fundamental to the workings of electricity, I didn't realise that you didn't know this stuff.For example we have quoted for 500ma per channel, what if either in the firmware or in the netduino code I set the output to 50%? Does the circuit just take what it needs, does the additional power create issues or is this wasted in the form of heat output from the power supply?
The way mankind uses electricity is normally at a constant specified voltage, it could have been current but we like voltage.
Loads are often characterised as an impedance or resistance. Sometimes it is constant like a resistor often it is varying like an oven turning on and off or a monitor changing brightness.
When you connect a load to a nominal voltage they work together to find an operating point which is a voltage and also a current (and therefore a power and a resistance too). As long as the load doesnt draw more current than the source can supply then the source or power supply should sit at near its nominal voltage, the load at this operating point will only draw whatever current it needs.
So for a 5v supply.
A resistor 1 ohm will draw 5 amps.
A buck converter led power supply will draw roughly 250mA if it is supplying the led at 3.15V and 300mA.
the same buck converter at pwm of 0% will draw roughly 40mA (due to overhead of the chip and the gate drive) and put out zero amps.
If the buck converter is completely disconnected from the supply then the output voltage will still be 5v but no current will flow.
If there is a short on the board then a large current will flow, and the supply wont be able to provide the full 5 volts, fortunately your fuse will soon blow and completely disconnect the supply.
This is true.Also if say 15 channels were at 0ma with the 5v 11A supply, would this mean I could take the other 15 channels up to 1A per channel?
Just remember there is a difference between the power supply current and the output LED current. This is because you have a buck converter.
If you used a linear regulator instead of a buck converter, then input and output currents would be the same.
You have a power supply (wall wart) supplying another power supply (led driver) therefore there will be two operating points both dependant on what current the leds want to draw which is dependant on what pwm you set.
Sounds like a bargain.I have bought an Atten 858D+ as per Dave's web blog, although I bought before I watched his review and that made me feel like I got a good deal at £30 including postage.
Don't start with the big supply use your wall warts first, and start with smalller fuses test the boards individually. Put on a dimmer pot for initial testing.
George Best said.
I spent a lot of money on Women, Booze and Electronics. the rest I just squandered.
possibly misheard.
#40419 Powerful Aquarium Lighting
Posted by
on 29 November 2012 - 12:53 PM
in
General Discussion
Second thoughts I think they are a bit low to be useful. Dont worry about them but do wire up a current limited wall wart or something.I will get some low blow fuses like you recommended 100ma or so.
Something like that , turn on with the current limit set to say 40mA and the lights dim. then wind it up checking for too much warmth in the various components.I'm going to test with the 1A 5v I have and will probably run the boards at a lower output for testing, maybe 200ma or so?
I meant power resistors to initially sub in place of the leds. Just a few 2, 5 or 10W wired up to be one or two ohms. Until you get the control circuitry and firmware correct and tested you don't want to blow the leds.This being said I will need to add a few extra resistors for testing, I guess you would recommend creating some form of regulator then for the boards especially whilst using the wall wart.
I would wait until you are happy with the boards. I still dont like the 5v and also I think I have made a layout mistake with the 5 volt tracks. I don't know how critical it will be but it isn't optimal. We should really have two separate rails for the 5v. So the noise from the leds switching doesn't upset the micro or the analogue. The analogue 5v is already separate from the micro 5v but the micro is sharing a supply with the fets and therefore will be subject to unnecessary noise. Sorry about that, It only recently occurred to me. Ideally we would supply the micro with an output from a linear regulator which is nice and clean. Have you got a cro? Anyway we will see when the boards come back.I think I am going to get a 5v 20amp switching supply eventually with build in protection as listed above, so it will give me some scope for expansion or if I really wanted to push the leds. Plus I guess the fact its switching should make it a little more efficient when running at lower output right?
This seems good enough. But you may need to beef up the transistor and lessen the resistance to give say 500mA.http://www.zen22142.zen.co.uk/Circuits/Power/add-on.html
But you will loose a volt with this the current limiting, so just for testing start with 8-12v, put the current limiter, then put a standard LM7805 (or 317 + 2 resistors) and then you project.
the current limit should be selectable so maybe switch in/out a resistor. Make on setting 30mA to limit damage on board faults. and the other one 500mA, so you can actually test you channels and firmware, without burning anything.
#46554 Powerful Aquarium Lighting
Posted by
on 02 March 2013 - 11:39 PM
in
General Discussion
It's a shame I live on the other side of the planet, I am a sparky too so I could help with the wiring.
I have been scratching around for Electrical work and it has been a bit slow, but I have also been given a job reviewing somebodies embedded electrical project, It is quite interesting but I'm afraid my assessment is a bit damning. I didn't want this as I know how hard it is to finish projects let alone make them perfect. Anyway my client says don't hold back, they want the truth, and there have been more than a few failures in the field.
Hopefully this will lead into a replacement board, I want to go Arm m3 or maybe m4. 32 bit code yay. 8bit does get a bit annoying.
Node Zero, I'm not familiar with this term.
Sounds like you have big plans, you might have to resign your day job to implement them.
I made up 5 x Steff 0.4 they all work, my production techniques need refining, but each time I try a different way and learn a bit.
You have to manage it so that the solder pasted doesn't dry out before you finish placing. I think the vacuum pick up idea is good but I haven't managed to do it. RE. Mikes Electric Stuff.
All the boards work well, I have only mounted one of the version 0.4s. My lab has 3 led lights now, more than bright enough.
I added a switch to them so when they are turned off they draw just about 10uA.
#44356 Powerful Aquarium Lighting
Posted by
on 28 January 2013 - 04:28 AM
in
General Discussion
I guess you have noticed on the current limiter ps that the negative input is not connected to the negative output. Which is a bit unusual I suppose, but in this case it is correct. Remove RLoad from the circuit and replace it with your boards for testing. Your boards should have an input jumper with two wires, these connect to where the load resister was. If you are worried about polarity, don't, we should have reverse polarity protection, give it a try. If it is wrong the current limiter should kick in. If that fails then the fuse should blow. If the fuse doesn't blow and you have 5 volts on the input pins, then it will mean that you can start testing firmware. Initially you dont even need to insert the Attiny chip. However when you insert a chip make sure the power is off. As to what size wall wart you will need 9-12V dc, regulated or not wont matter. The current limiting psu should be ok with anything under 20v. Dont use a battery!!! use a wall wart 500mA to 1A is best. Batteries can really damage stuff and start fires if there is a short. A car battery is capable of 100s of amps whereas a wall wart will only give 1 or so amps. I have never built this circuit myself mind you, but I am sure it will work if you have the wiring right. While the circuit is switched on use your fingers to check for abnormal heat output from the different components, also if you hear or smell something strange then turn power off and check things.
I cant seem to get motivated to solder my own Steff4 boards yet. Maybe soon. I think I am going to do it in two steps. All the numerous hardy components first and reflow them. Then all the rest and reflow the entire board a second time. I find if you are too slow the paste dries out and isn't as sticky. Also have a quick reference board already done, so you don't spend too much time wondering which resister goes where.
I don't actually use the liquid flux, but I think it is good for difficult ICs. Did I give you a link to Mikes Electric Stuff? Hes a one man SMD factory.
#43131 Powerful Aquarium Lighting
Posted by
on 10 January 2013 - 09:22 PM
in
General Discussion
For some reason we don't pay our VAT (10%) on items below $1000. And buying overseas is the norm for any serious purchases.
House negotiations are not going my way, out of the £11k devaluation the bank imposed, I'm currently fitting 8 of the 11
Sorry I dont understand, but then I don't know much about buying houses. I would take care as it is such a huge purchase.
Get some reflow practice on the hardier components first,
If you want a challenge try DFN with a thermal pad and no solder mask between the pads. That's what I did for the Solar charger. Each one took about 5 goes. Once you get the hang of it, it gets easier.
I must admit I found 2 soldering irons easiest for the big inductors.
#40485 Powerful Aquarium Lighting
Posted by
on 30 November 2012 - 09:12 AM
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General Discussion
#37418 Powerful Aquarium Lighting
Posted by
on 19 October 2012 - 08:48 AM
in
General Discussion
Attached Files
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steff35v.zip 44KB
6 downloads
#37401 Powerful Aquarium Lighting
Posted by
on 18 October 2012 - 10:03 PM
in
General Discussion
#30125 Powerful Aquarium Lighting
Posted by
on 02 June 2012 - 11:17 PM
in
General Discussion
#31702 Powerful Aquarium Lighting
Posted by
on 07 July 2012 - 01:54 PM
in
General Discussion
Thanks for pointing out the missing caps from my BOM, it was also missing R1.
All the caps are just decoupling or filtering caps of 100n 0805 and the Resistor was just a 10k 1206.
I cant believe I made this mistake, It just goes to show how easy it is. I am definitely not a computer.
I haven't gone exhaustively through your list as it seems your not quite decided the best way to go anyway.
As far as boards go I would go the modular approach, so if a board fails you can have spares, x channels per board.
Maybe 3, maybe 8, maybe 16. Design decision.
Also that way you could have some boards at 12 volts some at 5.
Actually on the subject of design decisions, the way just about every project I have worked on has been is that you never design it right first time anyway.
So there is no point trying to perfect the initial design. The moment the first working version comes out, somebody sees things that they hadn't noticed before.
So I think,
- Get something out there,
- Get something out there that isn't impossible to change or fix.
- Keep changing it till you think it's right.
I am writing as I think so the conclusion of what I think you should do is 3 channel boards (wait till I confirm that the design works) start with 5 or 12 volts, (your decision) and see how things go.
As far as 5 or 12 volts for 1 led.
5 volts can be slightly more efficient but, will it always be one led, because you can't easily change it.
If you go 5 volts you may have a noisy supply to the micro, this may or may not be a problem for the Current sensing on the Attiny.
If you go 5 volts you don't need the step up bc847 and it's two resistors. But you do need a different, logic level FET, just like AHellene's circuit.
5v you can use a smaller inductor.
I would use 12 volts but there could be a case for 5v and event a case for 7 volts.
If you want to use my circuit with 12v
just use a different TVS (12v operating voltage).
and remove everything including C3 to L2 reading left to right on the schematic.
Jumper the 24 volt rail to the 12volt rail.
If you want to use my circuit with 5 volts.
just use a different TVS (5v operating voltage).
and remove everything including C3 to U1 reading left to right on the schematic.
Jumper the 24 volt rail to the 12volt and the 5 volt rail.
you don't need the 3 x step up bc847 and short r13 to r15 and open circuit r16 to r18
It gets a bit harder as you may need a clean supply for the micro. I don't know.
Personally I wouldn't bother. It probably would be ok, but I think 12v will give you what you need.
No the netduino can only source less than 1 amp.Do you think this side of the circuit can be powered practically off the netduino
I would power the netduino from my 12v supply. Maybe via a resistor to just take away a bit of the heat.
That is a mistake, it was left there from some other current sense resistor that I had considered, please disregard.Also one of the resistors is marked as a bit wide, is this the foot print or the value and does it matter?
ps. You probably don't want to populate r28,r29, r30, I just put the footprints in for emergencies. I think 100mOhms if the lowest we could go anyway.
Also you don't need R12, this is also a contingency footprint.
You will loose very little running 1 led at 12v vs 1 led at 5. Only really in the higher series resistance of the inductor because you need a bigger inductor.Perhaps even provide a jumper option, where by you can select 5v or 12v and swap out the power supply accordingly?
Just run at 12v.
Steff shield is currently running 3 channels of 7 leds at 24 volts and at about 500mA. (XTE warm white) No heating problems on the shield and very little heat sink on the leds.How many ma are your running your Crees at in this circuit?
I will do 7 leds as well with my 24 volt prototype.
I want to move to 24 - 48. but will probably have to settle on a 24-36v version and 36-48v version, the black regulator doesn't have a wide input range. I just need to change a resistor value to switch between the two variations.
One thing that will work for you is the input circuitry on the Dimmer channels, you should be able to put your square wave straight in.
The input filters use 10k and 0.1uF which gives 166 Hz. If you can give it a pwm above 15KHz then your filtering is done.
BOM is corrected, thanks for finding the errors.
Attached Files
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Steff2 BOM.zip 4.01KB
2 downloads
#28258 Powerful Aquarium Lighting
Posted by
on 28 April 2012 - 10:47 AM
in
General Discussion
#27976 Powerful Aquarium Lighting
Posted by
on 23 April 2012 - 11:28 PM
in
General Discussion
Glad it is going well.
The good news for me is my NCL30160 boards finally arrived, so I may as well power them up.
I am going to do it at 24 volts and put Transient suppressor diodes on the inputs for a bit of protection.
I will let you know how it goes.
OnSemi assured me they tested the chips and said it was probably overheating.
If you look at the photo I posted on the SteffShield thread you will have to agree with them.
But as it is decision time for you, I will give you some thoughts becasue as you know proscrastination is the enemy of success.
I would go 12 volts per channel and use a mains down to 12v supply. This means you can add extra power to any channel if you need it, but you will need the single inductor per channel.
I like the meanwell supplies and I would get one that is highly efficient, this doesn't mean super expensive. ie. higher than 90% at rated current. Try a recent model of the meanwell ones.
The one in you picture looks ok but you really cant tell from a picture.
As far as Amps go .What other parts do I need and what adjustments need to be made in terms of the power supply?
Work in watts and then at the last minute divide it into amps.
Add other power requirements and led requirements.
the leds will be say 30 x 3 watts = 90 watts
other stuff say 50 watts???
= 140 watts
add some spare capacity and you have say 250-350 watts.
divide by volts and you have say 25 amps.
so that is a fairly hefty supply.
ps. I know this sounds like a computer psu but they aren't very efficient.
you can probably add extra amps later if you really need to.
the NCLs with the inductors in the standard circuit will limit the current and the voltage to appropiate levels.So do you think this is powerful enough for the 30 channels if we base on 30 Cree xp-e 3watts leds? Or would you suggest a high voltage perhaps 12v? I'm just mindful about you saying the NCLs operate better with lower voltages and that I will just be wasting power with high voltages as my leds only need upto about 3.5v max.
just a pullup resistor. the tlcs need to put out a square wave <= 20khz, I assume they can do this. you better check.Finally what additional parts will I need to take in to account the PWM from the open drain of the TLCs?
Just need the standard NCL circuit, running at 12v and definately use a nearby TVS diode with an nominal operating voltage of 12-24v and a let through voltage of 27-32 volts. like this SMA6J24A-TRAlso do I need any current limiting circuits and if so what parts would I need?
Also you need anti static wriststrap connected to earth to use the NCLs and dont take them out of the silver bag until you have your wrist strap on.
I tried a value of 33uH for the inductor, use surface mount for the diodes and caps so you can put them really close to the pins.
In order of component closeness to the chip
1. caps ceramic (smd, if possible)
2 diode
3 inductor
4 resistors
5 caps electrolytics if any
the other thing I have found is that I am using the new Cree XTE leds now, at around 2 bucks each without the aluminium backing.
Last night I sent off a design for my own mcpcb, to mount them, this should cut costs a lot.
They are rated to be very similar in performance to the XPG but 1/3 the cost. so I bought a 100 of them.
No worries about helping, good luck, I just hope you have better luck with the chips than I did. (Luck? It may have been incompetance)
#26779 Powerful Aquarium Lighting
Posted by
on 09 April 2012 - 02:15 PM
in
General Discussion
You just need over current protection.
This will give you
less losses
very simple circuit
excellent linearity, good for colour.
but at a cost of
fair bit of software fiddling if you change the leds per circuit, or supply voltage, if this is the case you will have to reset the max pwm
you will need fuses too, to protect your leds. make sure the fuses blow before the leds.
Have you worked out how many channels of how many leds?
Is it 32 channels of 1 led?
For the single led channels I don't think I would bother getting an inductor either.
just something like.
tlc -> PMD3001D -> nfet gate.(logic level fet, or maybe STN3NF06L)
and VCC - fuse - leds - nfet drain and nfet source to ground.
or VCC - fuse - leds - inductor - nfet drain and nfet source to ground.
| |
|--- diode --------|
Obviously prototype first.For my purposes ( domestic lighting 10 leds in series) I am going to rejig the Attiny461a, finish, improve the code, and choose the best transistors, and fet.
Maybe even go synchronous.
#32016 Powerful Aquarium Lighting
Posted by
on 14 July 2012 - 01:03 PM
in
General Discussion
I made some changes, added to new column that flags the changes.Please can you confirm that I haven't made any mistakes?
I left the inductors at 100u you can probably go smaller as well, probably down to around 10u. So many variables to choose these. 100 will be fine if you have them but say 33u might be better, but only marginally.For the 5v version, you mentioned I need a smaller inductor, can you recommend any that would be good for the job? Or will either of the ones I all ready have do the trick which seem to be 100uh and 330uh?
Look for operating voltage of 5v, but since you are providing a regulated low noise supply off board, the only thing this will do is protect against reverse polarity.You also said I need a different TVS diode, what would you recommend for this? PS I am probably going to order from Mouser in the UK.
Also bear in mind that you need to provide the regulated low noise supply off board because this is what the 12->5v part of the supply was doing.
No the sense resistor is about right, it will be ridiculously efficient but may be prone to noise.I guess the current sense will change in value right? Do you have the equation for 700ma from a 5v input?
You may want to try 200mOhms. I tried to layout my board inputs as "kelvin" inputs. Unless you do this well your current sense inputs will be prone to noise.
Any prototypes you may want to use up to 500mOhms.
Calcs: 100mOhms at around 700mA the current sense should read .7 x .1 = 0.07 volts at full load.
We are not getting all that 700ma through the sense resistor so say we get 500mA. ( Some goes through the Shottky). = 0.05v
then we multiply by 32 in the internal gain stage = 1.6 volts. our full scale may be 3.3 volts so we get a reading of 500/1024 at full current.
Your pwm outputs should feed straight in to these as long as they are 5v full scale. Dont connect the 5v but connect the rest.Finally the parts for the dimmer channels, are these already on the BOM and do the values still stand for 5v?
Apparently they are in transit.Have you recieved your boards yet and got one soldered up?
I have the parts from Digikey. The murata inductors look a mess, they must've been made by the apprentice. The last ones looked great.
I have also got some really fine prismatic diffusing glass on order, it breaks up the leds nicely. The plastic ones are good too but they look shit when they are turned off.
Good luck
Attached Files
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Steff2 BOM revised for 5v.zip 4.88KB
1 downloads
#32580 Powerful Aquarium Lighting
Posted by
on 23 July 2012 - 11:44 PM
in
General Discussion
#32978 Powerful Aquarium Lighting
Posted by
on 01 August 2012 - 01:29 PM
in
General Discussion
they seemed to be $6.00 each or was that a pack of something.Found these they seem relatively cheap and available what do you think?
Try PCE3340CT-ND I think you should be able to get something for around 50 cents, you can probably go smaller 33uF on these if you want.
from memory it is in devices and called cp1In terms of the cap symbol, which library do I need to look in?
Also you mentioned in terms of the library that I may need some files? Do you think this is the case and is this for the PCB design as opposed to the actual schematic?
more so in pcb editor, these is an excellent pdf that is built into the toolbar on pcbeditor. use that to help find footprint names
I have the channels 1 and 2 current sensing and stable.
Now I have init/boot problems and channel 3 I cannot get to current sense.
#32960 Powerful Aquarium Lighting
Posted by
on 31 July 2012 - 11:44 PM
in
General Discussion
This is just a bypass capacitor for the whole board. It's size depends on the power used by the board and the length of wire to to power supply and the power of your power supply.C21 larger electrolytic capacitor of 50uF, I have been unable to find a suitable part even in stock on digikey, am I missing something or is this a fairly heavty cap? Can you suggest any examples any where?
Anything from 10uF to 220uF would be fine, I suggest 50uF but it wont make a difference.
Also its voltage rating doesn't need any high voltage either. 16v is fine but 25v is good too. Remeber it is electrolytic not ceramic. For a computer analogy, the ceramic is like your ram and the electrolytic is like your hard drive. They are often in parrallel. It should be easy to find. The pdf schematic component is wrong is should show a curve on one of the plates and a plus sign. They are unipolar and need to be orientated correctly.
Yes that is fine.Almost there with the schematic, although I have just been changing the values of the components is this ok?
The diagram looks good otherwise,
dont worry about the DRC on those last things, you can safely ignore it.
If you really want to fix it you can edit the module and then edit the pins to be power in or whatever satisfies DRC.
Both of those are standard (12 mils x 6 mils) and (8mils x 5mils) dimensions with mils being 1 thousandth of an inch.On the topic of foot prints is there a standard for all the resistors I remember you mentioning an issue you had 0805 and 1206 I think?
Don't go any smaller than 0805 and I would use 1206 out of choice as it will be easier to measure and fix. I used 805 on the caps so I could fit them in nice and close to the ATTiny,
and 1206 on most of the resistors. When buying another thing to watch is the tolerance, but in this case it doesn't matter too much. Though it is easy to get 10% on ceramic caps and 1% on resistors so I wouldn't settle for less, incase you have spare and want to use them on another job.
After that I reckon you are done.
Now assign and/or make footprints and do the pcb layout. I find there is a fair bit of back and forth between metric and imperial while I do and check foot prints.
But I still haven't got the firmware to do the differential ADC inputs, with the 32 x Gain,
I have measured current but only as a one sided input, and because you get no gain I only get a tiny voltage.
I will try again tonight. My feeling is that it should work so it is only a matter of time.
#32917 Powerful Aquarium Lighting
Posted by
on 30 July 2012 - 11:17 PM
in
General Discussion
#32606 Powerful Aquarium Lighting
Posted by
on 24 July 2012 - 10:32 AM
in
General Discussion
You can't use the FDB3502 at all! Not at 5v.
This is a N Channel normal level mosfet. I am driving this at about 11 volts on, 0 volts off.
You need an N Channel logic level mosfet. You will drive this at 5 volts on, and 0 volts off.
Get one in the same package size (DPak, D2Pak)
, with a roughly similar Gate Charge Qg ( 10-30nC) lower is better.
and a low RDS on. I marked it in yellow because it needed changing. Sorry for not making this clearer.
If you used the FDB3502s they would still work, but they wouldn't switch fully on so they would have a higher Rds.
The net result is they would run hot and waste energy.
I can't remember what you want the 1u for, it probably wont hurt. Is it C1? For decoupling the power input pins of the attiny. If it is I have used 1u ceramic.I added in the capacitor that was a 1u to my BOM
I don't follow your question. Sorry did I leave it out of the BOM I sent you? It definitely needs to be there.
Edit: Confused gate capacitance with Gate Charge
#26773 Powerful Aquarium Lighting
Posted by
on 09 April 2012 - 12:54 PM
in
General Discussion
They are Junk!
I had my last one running this afternoon, and for one hour it was fine.
I went away and came back in another hour, my workshop was smokey and chip number 5 had gone short circuit. It was only running at 130mA and the chip was running cool. It did actually run very cool for the work it did. I once had it up to 800mA.
I initially had 29 volts, 130mA running into the chip but now I had 450mA running into it (I didn't read the voltage but It would have dropped to about 3-6 volts at a guess).
My current limiting supply had gone into limit mode and I had 450mA running through a breadboard to my chip. The heat in the chip was making the smoke and now it is stuck to the breadboard, I will send a photo, soonish. My smoke alarm didn't go off, it only goes off for normal cooking smells. sigh.
The only excuse I could find for this chip is that the circuit was breadboarded, and you shouldn't do this at High frequencies, but I dont actually believe the breadboarding of this circuit was a problem.
In short the NCL30160 is junk. Dont use it for your own safety.
If you look at the block diagram the short seems to be in the built in voltage regulator.
A timely reminder to take precautions when doing power electronics,
- smoke alarm
- current limited supply
- fuses
- watch closely
