Another SMD lebowski PCB

BTW, is there a list of all the different power boards that this goes with anywhere?... and I'm interested in which one everyone is planning to build to mate with this.
 
Sorry Progrock, with this you are at the bleeding edge of development for the Lebowski controller. Bob had developed a plug and play MTI 6 pak chip based power board with sensors and gates on board. While I have the kicad project for this it will be a while before I can produce this for myself.

you should be able to role your own or tie in others work like zombies, arlin and animalector or even the standard diy approach that Lebowski demoed in his build your own thread.

I suppose taking the modular approach to its logical extreme it might be good to create separate interconnecting pcbs for the gates and the sensors and the fets.

That way variants of each could be mixed and matched depending on the power requirement and parts easily swapped out for repairs and upgrades.

That for me is far off.

I am just waiting to get all the parts in from china and begin my journey into smd reflowing and pick and place.

Not a bad question though, thanks for raising it.

also here is a kicad 3d rendering of the mti powerboard bob designed.
3d view underneath.png
you can see bottom left as you look at it, that's where the brain board will fit in.
 
Oh, I thought it was mentioned that this board was made to be relatively easy to link to the power boards that were already made (maybe i misinterpreted the first post)... either way should be interesting.

whereswally, BTW, did you not see my previous post (last one on the other page).... you brought up a minor tweak that was done to the PCB design... do the files on the front page reflect that?... if not, could you share the updated design/gerber files?
 
progrock said:
whereswally, BTW, did you not see my previous post (last one on the other page).... you brought up a minor tweak that was done to the PCB design... do the files on the front page reflect that?... if not, could you share the updated design/gerber files?

sorry must have missed it, The boards should be the originals before Bob's tweek, I made a boo boo when sending off the gerbers to PCB way and sent Bob's original gerbers, they produced the PCBs before letting me correct the solder mask stencil which was for the newer edition. so I then reversed the component placement on the current Kicad project to produce the stencil for the older edition board (same as in the initial post by Bob)

Long and short of it, these SMD boards are identical to what Bob previously had made and sold. If I get through the 200 I've ordered I will go onto the newer edition but because I am reflowing the parts and not soldering them I shouldn't have the issue that bob was worried about. I wont be providing the gerbers until I recoup the money I have spent producing the boards. hope you can understand my position.
 
whereswally, yes, I totally understand. But again, I'm asking if you have the PCB design after the tweak... and if you could post those files.
 
whereswally606 said:
Sorry Progrock, with this you are at the bleeding edge of development for the Lebowski controller. Bob had developed a plug and play MTI 6 pak chip based power board with sensors and gates on board. While I have the kicad project for this it will be a while before I can produce this for myself.

you should be able to role your own or tie in others work like zombies, arlin and animalector or even the standard diy approach that Lebowski demoed in his build your own thread.

I suppose taking the modular approach to its logical extreme it might be good to create separate interconnecting pcbs for the gates and the sensors and the fets.

That way variants of each could be mixed and matched depending on the power requirement and parts easily swapped out for repairs and upgrades.

That for me is far off.

I am just waiting to get all the parts in from china and begin my journey into smd reflowing and pick and place.

Not a bad question though, thanks for raising it.

also here is a kicad 3d rendering of the mti powerboard bob designed.
3d view underneath.png
you can see bottom left as you look at it, that's where the brain board will fit in.

Basicly the brain board is opto isolated from the driver board and you build your own driver board right?
 
Have you guys seen these "DirectFET-L8" packaged.. or similar, MOSFETs?... they seem to be on a whole different level than the "standard" TO-220 FETs. They are really small, extremely low Rds, and some have some pretty damn high power dissipation values. On top of all that, dual sided cooling.... and so efficient, significantly less heat int he first place it seems (I suppose at the smaller size, they may get hot, mainly because you could pack so many together).

I'm sure these are only 1 package of many in the newer generation of FETs. Would be very interesting to see a power controller utilizing these. Considering how small a board like this SMD is, compared to the "old school" thru hole boards... could probably make one hell of a serious controller in a small package, with less of a need to worry about over heating.

Sadly I'm not at the level of designing something to utilize these yet... tho I wonder how practical it would be to attempt to simply take a thru hole board like the ones designed for the lebowski, and just minimize the size with comparable SMD components. I imagine that may work.. but I'm also guessing that if you really wanted to utilize these newer tech devices, it would be better off redesigning things based on what's available now, that wasn't in the past.

Either way, definitely some interesting stuff.... hopefully someone much more advanced than I am will be up for the challange.. and be generous enough to share with us.
 
progrock said:
Would be very interesting to see a power controller utilizing these. Considering how small a board like this SMD is, compared to the "old school" thru hole boards... could probably make one hell of a serious controller in a small package, with less of a need to worry about over heating.

Have you seen the VESC 6?
b25516f8f38ad330661b7f22534e0475041107ac.jpg

It's quite a compact design. I haven't used it personally but I have heard good things about it. The drawback seems to be that the heatsink has to be custom machined - it's more complicated than heatsinks for TO-220 mosfets.

vesc-heatsink.jpg
 
I mean that looks all nice and advanced etc, but will be extremely hard for the average hobbyist to build at home. Me for instance I have a 1960s soldering iron, all this small SMT stuff is undoable.
I am thinking about designing a simple all through-hole 6 FET powerboard to go with Bobc's processor board. Something that follows my low inductance strategy. Izeman gets 150A peak phase (100A rms) current with 6 TO247 4468 FETs. Should work upto 80V or 20s. Something simple to solder with no further hand wiring required.
 
Lebowski, that would be amazing... definitely a fan of your work. But, I will say.... SMD is not so hard to solder... maybe the insanely small stuff, but anything from 0805 resistors, and up is not bad at all (especially 1206 and above, but 0805 isn't bad)... as well as comparable sizes of other components. With something like the $50 TS100, a flux pen, and a pair of decent tweezers (honestly I was using $2 ones on my last SMD board, which were good enough), it wouldn't be hard at all.... I actually felt it was easier to do than some of the thru hole boards I've soldered, and I'm being honest. I don't have a microscope either... tho I did make use out of an articulating LED magnifying glass + light, it helped a lot.

Anyway... my point being, you should maybe consider utilizing some of the larger SMD components... they are actually surprisingly easy to solder, they are very cheap, and could probably reduce the board size by close to half. I think the 0603, and especially the 0402 and smaller stuff is where it gets much harder to do by hand... I know there is always solder paste, but I have yet to use the stuff.... if I was producing many of the same board I might, but for 1 off DIY stuff, I do it by hand.

TBH, I was completely afraid of doing SMD soldering till I saw this video: https://www.youtube.com/watch?v=b9FC9fAlfQE ...I personally don't really use the wipe method exactly... but still learned a lot. He uses a monster size iron/tip for pretty damn small components, without any problems. After watching the video, I no longer use the stock round tips... and realized the tip can be much larger than each individual pin you are welding, but with flux and a light touch, the stuff practically solders itself, as well as fixes any minor alignment issues almost automatically (it's so strange the first time you do it... but my first SMD board came out not only looking good, but functioning perfect on the first try).

Either way... I would be beyond happy if you designed a power board to go with this board... whether it's 100% thru hole or not. But I think it could really benefit if it was partially SMD.
 
ElectricGod said:
Basicly the brain board is opto isolated from the driver board and you build your own driver board right?

I don't think the bobc brain board is opto isolated, its basically a smt clone of everything on the original Lebowski board minus the drivers and current sensors. But you are right about having to build your drivers and current sensors on your power board. Fortunately Lebowski and I will be both producing a compatible board in the future. His I believe will be through hole to help the home gamers and mine will be smt mti 6pak based (on bobc's original design).

I will keep a stock of both powerboards, please don't let this stop people designing their own.

Lebowski has agreed to sent me his design once complete to build and test the bobc brain boards. I will do this on my scott ransom dh bike with a magic pie motor. (on a bench first before hitting the road too)
 
progrock said:
Have you guys seen these "DirectFET-L8" packaged..

just looked these up and arrive at shane colton's blog, he was building his "direct drive" board and states that he hadn't used direct fets till now since he didn't have access to a reflow oven. btw he is giving it ago with a hot air gun. I think though that there is a lot of chance to bugger this stuff up when you don't know what you are doing. Shane does. I don't yet but am learning and I will test all my boards before customers get any. MTI 6 packs boards can be hand soldered, that's why bob and I settled on them for the emax scooter power board.
 
Oh, very interesting... I didn't think about whether or not it could handle a quick hand solder... but good to know. Just slowly getting into using SMD parts in the first place... did not expect them to be as easy to handle/solder (up to a certain size) than they are... but not very aware of their difference characteristics/abilities. In general, I've jsut been considering them a small, sometimes less expensive, equivalent of their Thru hole counterpart (which I suppose is more or less true plenty of the time)... though I have seen a few cases of 2 parts having almost identical specs, one SMD one Thru hole.... but under the same conditions, the SMD was blowing regularly when the Thru hole wasn't (referring to a diode in a DIY spot welder I built... but assuming this may happen somewhat often when trying to do a 1 to 1 conversion).

Been considering purchasing a microscope recently (been eyeballing the AmScope SM-4TP or SM-4NTP)... and also been kinda wanting an Oscilloscope (looking at the Rigol DS1054Z)..... was leaning towards the Microscope first... though just found out that you can "hack" the Rigol and unlike every software upgrade (which also includes unlocking hardware features, I believe even turning the 50Mhz Bandwidth into 100Mhz, among a lot of other features that usually cost A LOT)... Both are on a bit of a sale today... debating on which one will be more useful in the immediate future.
 
spent some time yesterday doing the reflow toaster solid state relay controller heating loop.

At first I was having issues with uploading to the cheap v3 nano. problem was caused by having 328p rather than 128 setting for the chip.

once id gotten past that I had issue with the 5110 screen I am trying to use to mirror the serial output of the Arduino to tell me the current temperature of the max6675 thermocouple. I had that working reliably so I went on to interfacing the thermocouple.

I managed to get that working and showing the temp every half second to the 5110 screen, then I added the SCR to the mix and I was getting weird outputs on the 5110 with nan on the output of the thermocouple.

even had
"hello! use the flash library to use ram for storing ..." which I haven't looked into why that was coming onto the screen. So in short yesterday I got the screen outputting, I got the thermocouple outputting, I even saw the SCR going on and off but not all 3 working together, as yet this isn't a reliable system but it will be. Just need another few hours debugging and cutting down code from 3 different sources. temp was 7 degrees C in my outside office so I gave up on health grounds last night but the progress was happening albeit slowly.

mostly debugging Arduino code is a pain as the ide isn't anywhere near as complete as visual studio for c++. no intellisense. When its working I might do a vid and post up the source.

**EDIT**
Just reread
http://www.avdweb.nl/arduino/hardware-interfacing/nokia-5110-lcd.html
which I borrowed some of my code from. I think my 5110 is the flaky part which is automatically resetting the nano when the code is detecting an issue. that is messing with the control loop for the thermocouple

will got back to the original code without the 5110 screen and just get that working first.

***EDIT***
just been hammered for £54.16 extra in vat and disbursements fee by dhl. should have just split the items and stayed under the limit for china post instead. lesson learned. Wont be combining my packages again.
 
Actual progress this time and some pics to prove it.

IMG_20171203_163718.jpg
toaster oven and nano v3,thermocouple and shitty 5110 nokia screen

IMG_20171203_163735.jpg
close up on screen

IMG_20171203_163747.jpg
relay giving the toaster some juice.

so here are some annoying things. If the thermos couple contacts the metal of the toaster it must be shorting to earth causing the thermocouple to report 0 centrigrade but the nano doesn't crash.

5110 screen is not reliable

but the serial output to the pc is.

so at the moment I am running the nano through the Arduino ide and looking at the output its not bad but equally its not the curve id like for the reflowing. here is what I mean
graph of 1st reflow temp.png

ignore the heat at the start of the graph that is because I was having issues with the grounding of the thermocouple and the toaster hadn't cooled down from previous unsuccessful runs. Anyway, this graph shows red the real temp and blue the very rough target temp.
I am not sure the toaster oven is getting hot enough and also I'm not getting a nice transitions that id like. I think this is because the oven element is not powerful enough and doesn't respond well enough to the ssr relay. Another chap online was using a halogen circular oven with fan (slightly modified but nothing special) and looked to have a way nicer graph. I may upgrade if this toaster oven wont cut it. But at the moment I think its probably fine. I need to do a test run but I don't have bas' chip or the solder yet??? stupid post.
I also am waiting on a few other passives so need to do an inventory.

Also another project for me in the long run is to dip my toe into the world of open pnp (pick and place) hopefully that will take the tedium out of the manufacture of these things.

Anyway one more test now that the oven is cool again and see if this next minutes are better than the first.

Second test was worst than the first. I am convinced that the toaster oven i have has an internal thermal cut off at 201 degrees so no good for the 210 to 230 range for the peak of reflow. Have invested in a 1300w reflow oven as demoed on andy brown's webpage. £23 instead of £6.

He also has a couple of variants for the pid controller but I shall try getting close with what I have so far.
 
Bit of a set back, I had an order that I either cancelled my self by accident or had eBay seller cancel without telling me. So unfortunately the lm5017 and it's little bro lm5018 in soic8 package is sold out everywhere till march/April 2018. I have sourced ten from dicikey on eBay (Chinese seller) I don't know whether they are real or counterfeit but they are literally the only option till march/April.

I spoke to bobc's friend at Siemens to see whether they had any languishing on a shelf but I've not heard back yet. He did tell me that the market has gone mad and there are shortages everywhere in ic parts and procurement is now a massive part of his job. He blames the mobile and automotive sectors as they have a huge impact on demand.

Next project get halogen oven following reflow curve
 
Project stalled till March 2018 or until TI produce the lm5017. (Which looks to be march)

If anyone can make/design an adapter from TI wson package to soic8 then maybe it could be back on track. I'm sorry for the delays I've tried every option to get the missing IC but there are no alternatives without a board redesign or adapter board. The TI wson package equivalent of the lm5017 has a different pitch distance for the pins than the soic8

Anyway I have 10 on order which has cost another £54 so I'm financially commited.but I will understand peoples disappointment about the wait.
 
soic8.png
original

wson.png
newer as of today WSON .8mm pitch TI variant

So I conversed with Andy (animalector) and the consensus was a redesign was probably the least trouble in terms of boards.

I did this over the last couple of hours and the result it above. I think its ok, but I dunno, this is my first bit of rework in kicad.

Will get a very small run done of these 10 of and use the other stencil for this at the only diff is the one IC.

China makes pcbs quicker that TI make ICs

[strike]will probs send off design tomorrow.[/strike]
PCB on way, total cost of 15, £21
WSON LM5017 and mcp1630 on way from digikey 10 and 10 for £40 delivered (still have farnell back order for march)

So so so broke for Christmas. :(
 
tested the unmodified halogen oven last night with the same Arduino logic board setup. I can positively say that the logic to control the SSR (solid state relay) in that the led lights when its supposes to heat to the target temp and it goes off when the real temp is over the target temp. But the relay is powering the oven all the time.
The halogen oven will need foil lining and fan modding(to avoid blowing parts about) for use as a reflow oven but the results on heating so far are very positive.

Anyway i've been persuaded by reading andybrown's website to try using a dimmer switch instead of an on off relay. I have one that is hooked up to a 3pin wall socket on a 2x4 for use in controlling spindle speed of my router in the mpcnc project but I plan to remove or bypass the potentiometer and hook in a digital pot which I can control from the Arduino. In this way I should be able to provide a more subtle response (than on or off) by dimming the ac voltage based on the differential value of the real to target temperature.
already ordered my digital potentiometer so be playing again on the 15th.

It was pretty damn cold out in the shed last night so the halogen oven is a blessing. Need to get a tripod and camera setup and do some youtubing perhaps.
 
I once suggested a clothes iron for SMD soldering instead of an oven, Futterama had good results with this:
https://endless-sphere.com/forums/viewtopic.php?f=30&t=57375&p=985232&hilit=iron#p985225

Basically back in my Research days they were curing plastic chips with simple clothes irons, as the (old fashioned mechanical) temperature control was remarkably accurate...
 
that could be good too. I actually think ill be fine once i've got either a new relay on the old logic actually turning on and off the bulb on the halogen oven or the new SCR with a digital pot diming the bulb. I used to have an old clothes iron for redoing the wax on my snowboards.

I was even thinking of reprogramming a sonoff 10a relay esp8266 to do all the Arduino's job instead of having it all on a bread board but whatever works is what I will do. I haven't got all the parts yet so I'm not really wasting any time so far.

The nice thing is about the sonoff is that for $5 + thermocouple you can have a working safe reflow device controller (very little wiring needed) if I get that working ill do a "how to" on here.
 
Well that was quick.
Digikey parts (WSON lm5017) and the mcp1630t-i have arrived already as did the
Farnell mcp1630t-i but not the lm5017 soic8 part.
Still waiting on the new pcbs from pcbway before I can do anything really. but its looking promising now

waiting on my digital pot but will do some trials by hand rotating the scr pot on the dimmer I will use and mod the halogen oven to increase the insulation and turn down the fan parts.

amazing the cost of these things really given how tiny they are.
 
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