My schematic, couple questions.

Shafto

Senior Member
so here it is:


and the code:
Code:
main:
	readadc 0,b0

	readadc 1,b1

	readadc 2,b2

	b3 = 4

	w1 = b2 * b3



  If pin5 = b4 Then             ' No change in pin 5
    If b4 = 1 Then              '   Pin 5 is high ...
      PwmDuty 1, b2             '   ... Update duty only
    End If
  Else                          ' Pin 5 changed
    b4 = b4 ^ 1                 '   Update b4 to reflect pin 5
    If b4 = 1 Then              '   Pin 5 went high ...
      PwmOut 1, 255, w1   '   ... Start PWM
    Else                        '   Pin 5 went low ...
      PwmOut 1 off            '   ... Turn off PWM
    End If
  End If


	if pin0 = 1 and pin3 = 1 then flashhazard

	if pin0 = 1 then flashleft

	if pin3 = 1 then flashright

	if pin0 = 0 and pin3 = 0 then main



goto main

flashleft:

	high portc 7

	high 0

	pause b0

	high 1

	pause b0

	high 2

	pause b0

	high 3

	pause b0

	high 4
	
	pause b0

	high 5

	pause b0

	high 6

	pause b0

	high 7

	pause b1

	low 7

	pause b1

	low 6

	pause b1

	low 5

	pause b1

	low 4

	pause b1

	low 3

	pause b1

	low 2

	pause b1

	low 1

	pause b1

	low 0

	pause b1

	pause 50

	low portc 7

	goto main

flashright:

	high portc 6

	high 0

	pause b0

	high 1

	pause b0

	high 2

	pause b0

	high 3

	pause b0

	high 4
	
	pause b0

	high 5

	pause b0

	high 6

	pause b0

	high 7

	pause b1

	low 7

	pause b1

	low 6

	pause b1

	low 5

	pause b1

	low 4

	pause b1

	low 3

	pause b1

	low 2

	pause b1

	low 1

	pause b1

	low 0

	pause b1

	pause 50

	low portc 6

	goto main

flashhazard:

	high portc 7

	high portc 6

	high 0

	pause b0

	high 1

	pause b0

	high 2

	pause b0

	high 3

	pause b0

	high 4
	
	pause b0

	high 5

	pause b0

	high 6

	pause b0

	high 7

	pause b1

	low 7

	pause b1

	low 6

	pause b1

	low 5

	pause b1

	low 4

	pause b1

	low 3

	pause b1

	low 2

	pause b1

	low 1

	pause b1

	low 0

	pause b1

	pause 50

	low portc 7

	low portc 6

	goto main
My first one ever.. sorry if it's a little hard to follow. Here's the vid of it working: http://www.youtube.com/watch?v=fpeS-HkaYHU

On the top is the 5V reg with the suppression caps and such... everything bellow that that says 5v connects to this reg... thanks again for that schematic hippy.. just one thing though, the 0.22uF cap connected through the 47R, how many watts does that 47R need to be? just a regular old 1/2watt?

First question is about using the interrupt command for the brakes.. you see there is an empty input.. and I have another PWMout.. I am thinking that if my brakes are too bright maybe I would want to use the second PWM signal to drive them.. but using the interrupt if a signal light is on and I hit the brake, would it stop blinking? ..I suppose the best way is to code it in and check it out, but I wanted to look into the speed of things aswell... the way it's set up now the brake signal just switches the regs on full time.. so it's instant.. one of the big reasons why LEDs make great brake lights is the instant on compared to incandescent can save you 20 meters at highway speed... I don't want to negate that advantage by putting the brakes through code and slowing down the response... so how much slower would an interrupt be than what I have wired right now? ..I can always stick with this and just go with bigger resistors for the LEDs if I think I need to dim them down a bit.

Second question is about the +12v inputs.. This is something I hadn't thought of until I drew up the circuit.. I don't imagine I can just feed these 12V inputs into the picaxe to turn on the signals or the markers... what's the best way to deal with this? switch some transistors connected to the 5v line? or use a voltage divider?

Thanks! I really appreciate all the help I've been getting here to build this project... couldn't have done it without you guys.

edit: the whole idea behind a 2amp fuse on each reg for the marker/brakes is that is one of them blows the load will be low enough that 2 regs can take up the slack and run a little hotter keeping the tails working until the fuse and blown reg are replaced (should the need ever arise) The whole thing is very over built.. I don't know exactly how many LEDs I'll be using yet, but I imagine I'll be drawing less than half the power available.

second edit: forgot to mention that the caps on the regs aren't included in the diagram because they're already soldered onto the pins SMT style.

 
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Shafto

Senior Member
all the replies are gone.. heh.. oh well... I'll update again.

I was having problems with the PWM pin just going high when I turned it off... it wouldn't do this right after downloading the code, it would work fine for a while.. and then all of a sudden when pin5 goes low and PWM turns off... the pin would just go full high and I'd get what the brakes look like... but it was definitely a signal still coming from the PWMout pin.

I added a 1k resistor to pin5 where it connects to +5 to switch on.. (as per the manual, didn't notice that before) and then the 10kpull down is still there too.

I also then added a 10k pulldown to the PWM pin to see if that would hold it low when it turned off to solve my problem.. but it didn't work... however, coupling this pulldown on the PWM pin while adding "low portc 1" after the "pwmout 1 off" command seems to have fixed my problem.. hopefully it won't randomly start happening again...



I still need to order some little transistors now to switch +5v to the inputs for the marker and signals when they receivce the +12v signal to do so... but I still have to determine if these things are ground switched or positive switched to see if I need NPN or PNP.... I'll go check that out when it stops raining.
 

Shafto

Senior Member
Ya from the crash...

I guess I should put the 4700uF after the varistor? since it's not going to be an X2 or filter cap capable of dealing with spikes.. just for brownouts.. so what would be the best position for it?
 

Shack

Member
Questions:

1. Why the Varistors and the choke?

2. How do you trigger the turn or brake lights? Pull the inputs to ground or?

3. Where did you find 6 amp diodes?

4. The ULN 2803 can only handle ~ 600ma. Why the 2 amp fuses?

5. You have parallel diodes from the brake in and pin 12 of the picaxe. How are you turning on the brakes???

I sent a PM as well
 

Shafto

Senior Member
Questions:

1. Why the Varistors and the choke?

To filter the power supply to the picaxe.


2. How do you trigger the turn or brake lights? Pull the inputs to ground or?

right now it's configured so that when the inputs go high the signals are triggered, I have yet to test the actual car to see if they are positive switch or ground switched... right now I'm set up for positive.. but I may have to change that.. no big deal either way.


3. Where did you find 6 amp diodes?

digikey


4. The ULN 2803 can only handle ~ 600ma. Why the 2 amp fuses?

500mA per channel, 8x5=4000mA... it won't be doing near that though.


5. You have parallel diodes from the brake in and pin 12 of the picaxe. How are you turning on the brakes???

When you hit the brakes pin 4 on the reg goes high full time.. turning it on 100% and the LEDs to max brightness... otherwise pin 4 might see nothing if no lights are on.. or just PWM signal for the markers... no matter what when you hit the brakes pin 4 goes high and the reg goes on.
 

Shack

Member
The brake will be a 12v signal from the switch under the pedal. So will the turn signals.

So you say you are providing a +12v signal on the 4 pin header to the Picaxe chip to trigger the various functions?
 

evanh

Senior Member
... thanks again for that schematic hippy.. just one thing though, the 0.22uF cap connected through the 47R, how many watts does that 47R need to be? just a regular old 1/2watt?
That's usually inside the resin package of the X rated part along with the self healing 0.22uF cap. They look to be 1 watt resistors.

The 4700uF cap is fine where it is. I'd place the varistor before the diode and the X part before the inductor.
 

kevrus

New Member
with reference to the +12v inputs into the picaxe (L/T in, R/T in and Marker), I would use opto-isolators, this eliminates any noise on the picaxe pins and is easy to re-configure if the 'car' switches the pos or the neg, i.e. using some jumper pins on the pcb as all it will be driving is the LED of the opto- isolator.
An excellent project.
 

Shafto

Senior Member
That's a great idea kevrus, I'd like to have it configurable for negative or positive switching.

I'll ditch the 47R on the 0.22uF X2, and I always wondered why the varistor should be the last line of defence.. I thought it should go first... the design is not mine, another member, dippy I believe, drew that up for me... I just thought that the 4700uF shoud go last though.. as it's not protected against spikes and such.. maybe just after the varistor would be fine though...

I've been thinking.. and I would like the brakes to be able to be dimmed by PWM a well so I can match stock brightness levels... so I will try coding in an interrupt for them, but if that disrupts the signals lights when they are on when I hit the brake I can't go that route, then I suppose I will make a PWM out of a 555 and send that signal to pin 4 of the regs when the brakes are on... we'll see about that.
 

Shafto

Senior Member
There are 2 X2 caps, what standard caps are already there? I don't quite understand what you're saying.

Also your link doesn't lead to any part.. just a distributor page.
 

evanh

Senior Member
Ouch, you might have problems with using those PQ09 voltage regulators. They have BJT outputs, it's not a good idea to parallel them. If you run separate power wires for each one then it might prevent thermal runaway.

Why 9 volts? They will get hot very quickly.

Also, they prolly won't take kindly to voltage spikes on either the input or the output.
(Excuse the multiple edits, I mistakenly didn't notice they were actually voltage regulators.)
 
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evanh

Senior Member
There are 2 X2 caps, what standard caps are already there? I don't quite understand what you're saying.
Oops, so there is, the small one can be a normal ceramic, I'd make it a 1 uF ceramic. The bigger one is merged into the mains filter.

Also your link doesn't lead to any part.. just a distributor page.
Interesting, Work-around supplied above ...
 

Shafto

Senior Member
I've been getting so much conflicting information from members here about how to filter the power into the picaxe.. i just can't keep up with it all. I went with a design suggested by Dippy and I think I'm gonna stick to it, or I'll never finish this.

I'm not running this off mains.. that filter seems like it's meant for an AC line.. not 12vdc. I already have both x2 caps, and was told both should be x2... I don't know the reasons for all of this but I really can't believe all the conflicting info on here people have about how to filter power... there really should be something done about that, confuses the hell out of beginners like me when you have 5 different people tell you 5 different things.

I don't know what a BJT output is but I'm not worried about it, I know many people who are using multiple versions of these regs in their vehicles with no problems, without even an input cap.. I have that and there's another varistor ahead of the regs themselves.. so they'll be fine.. how will they see power spikes on the other side? they're only running LEDs.. no motors or anything like that..

Very hot? hmm.. no, they stay very cool actually, what would give you that idea? they're dropping a bit of voltage but it's not enough to create much heat... each one is only running at half capacity and rarely delivers that constantly (only when the brakes are on) I don't even need sinks on them.. though I will put some on, I can hold them in my fingers with no heatsink and no issues... I used 9V because I want the arrays to be the same brightness always, if I had used 12V then the dropout of the reg while the car is off would feed the LEDs less power than usual.
 

BeanieBots

Moderator
Shafto, I can understand your frustration at so many suggestions but to be honest, I don't think there is much in the way of conflict. More a variation on options. If you were designing this for "on the bench" then very little of the filtering would be required. However, as has been frequently pointed out on this forum (with back-up data) the electrical supply in a car can be one of the most hostile environments a micro is ever likely to be put in.

At the end of the day, it is YOUR car and YOUR insurance that will be invalid if anything goes wrong.
The AC filter suggested by evanh is not such a bad idea. It's merely another alternative. X2 rated caps and choke all pre-built into one unit. As you correctly point out though, you need to decide on a design (from memory, the one by Dippy was OK) and get on with it.

"Other's" may well have built supplies with less filtering and got away with it. Another mile down the road and they might not. Do you KNOW how much crud YOUR car puts on the 12v line?
If the answer is no, then you need to design for worst case.
The advice given (much of which has unfortunately been lost) has been geared towards just that because anything less COULD fail given worst case conditions.
Hopefully, in addition to circuit and component suggestions, you have also picked up enough information to make an informed judgment.
All suggestions are made in good faith. Sometimes genuine errors are made but these are swiftly picked up and commented on by other members. I don't think there has yet been any significant technical difference of oppinion regarding what needs to be done. Just alternatives on how to do it.
All said and done, it's your choice.
 

moxhamj

New Member
Re "I went with a design suggested by Dippy and I think I'm gonna stick to it, or I'll never finish this."

I'd have to agree with that. The filtering is very over-engineered and sure to block all spikes I can envisage. I've got away with a lot less filtering than that in a car environment and haven't had any failures.

The other consideration is to think about how something might fail. If a spike gets through and zaps the picaxe then it will likely fail completely. If one of its jobs is to regularly update a display or change the brightness of a led on the dashboard (eg to indicate something) then you will see that it has failed instantly. I've designed circuits in the past that send out a 1Hz signal and then other circuits won't run if this 1Hz signal isn't present. A chip might fail with a line high or low but is unlikely to fail with a 1Hz pulse. Just flashing a led on the dashboard to indicate the chip is alive is probably more than enough.
 

evanh

Senior Member
Sorry if I'm a bit abrupt. I never saw the lost posts. Good to hear the outputs are running with ease.

The one change that you should make is to shift the 220nF X2 cap to in front of the inductor.


Cheers,
Evan
 

Shafto

Senior Member
I didn't mean to come off wrong there.. I really appreciate all the help here.

I'm not sure why I should move that capacitor, and all the little confusing suggestions I get about the filter are to achieve the same goal I'm sure, but when they are all different with no explanation as to why I have no basis to make a decision.

It would be possible for me to isolate each output on the regs, I was thinking of going that route anyway in case of a failure, it would be like 1 bulb going out, half the array would still work... but I want to know why? why should I not run 2 of these in parallel? I will review the datasheet, but I'm fairly certain there was no mention of warning against this.
 

BeanieBots

Moderator
Regulators have a voltage tollerance which can be as high as 5%.
So, the lowest output would be about 4.75v and the highest about 5.25v
If those were connected in parallel, the 4.75v one would not start to supply current until the 5.25v had been loaded so high that it's output dropped to 4.75v. At that point the 5.25v one would be overloaded and cooking.
(I did that for 5v but it's the same issue at 9v +/- 0.45v)

You MIGHT get away with it if all your regulators came from the same batch and have very closely matched outputs.

The big issue with your entire circuit is MIGHT.
It is very LIKELY that all will be well with your paralleled regulators and input filtering. Many people may have built that design and it worked in THEIR car.

Bottom line, there is no GAURANTEE that it will work.

It is NOT a suitable way of doing it for a safety critical device.
 

evanh

Senior Member
The purpose of the X2 cap is to soften any large spikes that appear between the positive and negative supply wires. It's going to achieve that best if it is placed before the inductor. The inductor itself is there for the same reason, it'll translate the spike into a much more gentle surge that the main capacitor will then store. The 1 nF X2 cap can be replaced with a 100nF ceramic as it is most useful for absorbing extremely small sharp spikes with little change in the voltage.

There is two transistor types: http://en.wikipedia.org/wiki/Bipolar_junction_transistor and http://en.wikipedia.org/wiki/Field_effect_transistor .

The point of interest I had was that BJT's conduct stronger when heated. That said, since they aren't turned hard on then that particular point is not relevant. But BeanieBots equivalent point about differences in the regulated voltage is a valid one.
 

Shafto

Senior Member
I had thought of that.. the different voltages, I have measured the ouput of all of them and 'binned' them myself somewhat.

for one side I have

8.91, 8.96 together for right marker/brake

8.94, 8.94 together for left marker/brake


8.97, 8.99 together for right turn

8.98, 8.98 together for left turn


I tried to set it all up the voltages would average, but like I say, I can design it with separate outputs so they are not paralleled which would be smart anyway, if one reg did fail half my brakes or half of my signals on that side would still work... The other way I was going to do it was to have them paralleled and then if one did fail the load would be low enough that the 1 reg could take over the whole array... but thanks for the info about BJT, I'll definitely be separating the outputs now.
 

BeanieBots

Moderator
If you have hand picked them to match then well done.
If you put a diode in series with outputs then it will help on several counts.
The series resistance of the diode will help to equalise the voltage difference and the current share. Also, should one fail, it won't pull the other one down with it.

I also agree with evanh about the placement of the X2 cap and for the same reasons. I'm fairly sure that's where it was on the original diagram.
Very rapid spikes will make a large inductor look like a capacitor (due to winding capacitance) so they need to be softened to let the inductor and large capacitor do their stuff.
 

Shafto

Senior Member
Here's the original diagram supplied by Dippy:

http://www.picaxeforum.co.uk/attachment.php?attachmentid=173&d=1193139252

the inductor is before the cap, but I'll change that since there's consensus on it operating better before the inductor... I think I'll leave the second X2 cap there though, there's a 0.01uF ceramic on the pins of the picaxe.

If I went with a diode on each output of the reg I'd have to buy all new resistors for the LEDs.. the amber ones run close to 3v each, so I'd end up running them derated with a 1ohm.. they already are only using a 5.1ohm, and I wouldn't want to derate them, as they're not as intense as the red/orange LEDs which are only around 2.65v I think I'll just run the outputs separated.. since the regs are so close anyways, there will be no noticeable difference in light output from each side of the array... I just have to run 2 more wires to each tail light.. no big deal.
 

BeanieBots

Moderator
Yes, that was before the X2's were added.
The cap in series with the 47R is 22uF not .22uF
It catches, dissipates and helps reduce ringing caused by longer surges seen by the inductor.
I would put an X2 before the diode to help protect that as well as being before the inductor. The resistive action of even the fuse combined with the X2 will have quite an effect on the high voltage short duration spikes.

I agree with your comments about the regulators if that is what you already have.
 

Shafto

Senior Member
I thought because the 150V rating next tot he caps that they should just be X2s, I believe I was told later on in the thread that is what I should be using there... my mistake about the 22uF/0.22 is the 22uF/47R needed? I thought I had this figured out.. now I'm lost again.

Why should I not just put the varistor ahead of everything? It's very robust, I don't see why it's a last line of defence.

..I'll draw it up again here reconfigured this evening.
 

BeanieBots

Moderator
The 22uF/47R will help keep ringing down.
I'd keep the varistor after the inductor because alternator overshoot (when high current devices are turned off) would give it good pasting if it was before the inductor. The inductor should hold off such events with the varistor shunting away anything that the higher value caps can't keep in check.
Remember, there are two key events going on. High voltage short duration and low voltage (around 100v) long duration (10's of mS).
Unfortunatley, the pdf which explained it all has also vanished.
Along with Dippy by all accounts! He's gone very quiet lately.
 

Shafto

Senior Member
I'm fairly certain the varistor was built to be put right on the alt.. all newer vehicles have a big main varistor... this one is a 20mm radial beast that can handle a 2KA current surge, or 12J of evergy.. I got the best one they had... but I'm all for giving it an easier life.. I've been busy here actually modifying my stock lights with LEDs... drilling over 1200 holes for the leads, cutting over 1200 pieces of little shrink tube.. shrinking it on.. mounting the LEDs.. and then soldering them all up... a lot of work... I'll post up a revised filter here for review as soon as I can.
 

Shafto

Senior Member
Well.. as I figured.. no matter how hard I tried to get everything together for one order I knew deep down I'd have to make another...

So.. how much better off would I be with something like this:

http://www.epcos.com/inf/30/db/emc_fi_06/b84110a.pdf

compared to my filter design now...

If I did go that route, I think it would be best to get the 500mA version because it has the most impedance which would offer better filtering? the picaxe won't draw close to 500mA anyway..

I could just keep the filter design I have now for breadboarding more picaxe circuits on my computer power supply...

I imagine the X2s and Y2s matched up with inductors in filter linked is probably a better option over all for the car?

And then a 100nF ceramic cap before the voltage reg aswell? high voltage rated? Here's an automotive one.. but it's pretty small SMD, I could do it though.. worth it?

http://search.murata.co.jp/Ceramy/image/img/PDF/ENG/GCM21BR72A104KA37.pdf

or maybe just a normal through hole 100V 100nF?

http://www.epcos.com/inf/20/10/db/cc_07/X7R_Leaded.pdf

I wonder what the benefit of the automotive one is...
 
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evanh

Senior Member
Can't view any of those pdfs :( but, yep, sounds good.

The 100 volt leaded ceramic should be fine. While the surface mounted ones are better performing electrically they are much poorer performing mechanically. Heat and vibration tend to fracture the bonding of the end caps of the surface mounted ceramic capacitors.
 

Shafto

Senior Member
I wonder why you can't view the PDFs?

The 500mA version has

1x 0.22uF X2

2x 4700pF Y2

2x 39mH

The 1amp is the same, but with 2x 10mH coils... plus the 500mA is PCB mount... so I think I'm better off with that one?

The one you posted:
# Capacitance, X type capacitor:100nF
# Capacitance, Y type capacitor:2.2nF
# Capacitors, X type No. of:1
# Capacitors, Y type No. of:2
Inductance:10mH

Which I could not find on digikey.. but I think the epcos one looks like it might be better?

..I don't quite understand the pins on the filter though.. you have L and N on the line side.. easy enough..

but then on the Load side there are 2 grounds and L and N again... running DC into this thing.. do I just ground N on the line side + the 2 GNDs on the load side and then use the N on load side as my ground from there on out? That must sound ridiculous without a picture.. let me printscreen this thing you you can see it.







I'm working on a whole new diagram right now... should be finished soon... I'll post it up.
 
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lbenson

Senior Member
>I wonder why you can't view the PDFs?

The first url has a "]" at the end of it. Edit it out and the link will work.
 

Shafto

Senior Member


Ok.. a little neater this time hey! it looks a little weird because I had to bring it into paint and make it smaller..

I've got jumpers set up on the opto isolators so you can have negative or positive switching...

I also did the same thing with an NPN and a PNP transistor for switching on the brake PWM signal to the regs... The marker PWM signal when on will just be overshadowed by the brake PWM signal when switched on.. Looking around i see that PMOS devices (16-25V) use 10.5k + a zener diode for the input of transistors.. so for 12-14.5V I figure a 10K should be good? should I also put a zener on the input to the transistor? 15V or so, or is it ok like that?

..The new schematic is a 40X1.. I just ordered one.. not really needed.. but I will probably add more showy type features later on... I want to add a couple mics or something and have the left and right signal act like amplitude indicators for for L and R sound channels in the stereo.. also some strobing effects to go with music on the LED reverse lights and brake lights... but I'll fiddle with all that later on...

So how does my Filter look now? The wiring of the epcos filter? I'm not sure about the 2 grounds and the neutral line.. what all should be done with that in a DC application.

The transistors? I'm just using 100mA guys here...

I've also added another ULN2803A in parallel with the other... some of the channels are pulling 280mA, per side, and if I put the hazard flashers on I would go to 560, exceding the limit of the ULN2803A per channel.. I only paralleled the first 6 channels... the last 2 are barely on for any amount of time before turning back off.. and there's only 280mA on with with both sides going, and only 140mA on the last channel with both sides... so no point is drawing extra power to when switching to parallel those channels as well.

Outputs from all Voltage regs are now separate.. and each is fused at 2 amp.

...everything else is pretty much the same as the previous schematic.
 
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BeanieBots

Moderator
You now have a grounding problem.
The 0v comming in to the power filter and the 0v comming out of the filter must not be connected together or the filter will be shorted.
Throughout your schematic, you have 0v connections which your diagram implies are connected to the input side of the filter 0v.

To help get your head around it, think of the filter as being like an isolation transformer and that it is essential to maintain that isolation. It should then become more clear how (and to where) all the 0v connections need to be made.
 

Shafto

Senior Member
I don't know how apparent it is in the schematic, but the N output on the Load side of the filter is not connected to the 2 GNDs on the load side... I have the 2 GNDs on the load side connected to the N on the Line side.. the load side N is independent... All grounds used in the picaxe cicircuit that run off 5V go to the N on the load side..

This is my first and only project, so if you don't see it here I haven't dont it.. heh.. I don't know what an isolating transformer is.. or how it's any different than a normal one. (a normal transformer isolated output from input anyway?)

Lemme see if I can do some editing here to clear things up.

Edit: ok.. hopefully it's more clear now... not that I'm sure if that's the right way.. but should be less confusing now...
 
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BeanieBots

Moderator
I'll try to explain.
The "N" on the input side and the "N" on the output can be at very different voltages. (the whole purpose of the filter).

You have connected the "N" on the output side to your regulator ground. That is correct.
You have connected the two grounding caps to the input "N". Nothing wrong with that but that node is also shown connected to a common ground bus. (the pointing down arrow).
This is a DIRTY ground.
All your chip 0v are shown connected to the DIRTY ground (the same symbol).
NOTHING is shown connected to the clean ground, (the one used by your voltage regulator).
Net result is that you now have a nice clean regulated voltage with respect to the regulator ground but your "general" circuit 0v line has all the crud on it.

An isolating transformer is one which simply isolates the input and output but keeps the voltage the same.
 

Shafto

Senior Member
maybe you posted before you saw my edit, I now have all the grounds in the circuit that run off the 5v reg connecting to the line side N ground... "dirty grounds" are now labelled "main GND"

Would it be better to attach the grounding caps to the clean ground, or keep it the way it is?

do I have everything in the filter in the right order?

Another thing I remembered.. I didn't realize the X1 parts had internal resonators.. I already have 2 external 4mhz resonators.. is there any advantage to external? or better to let it use it's own?
 
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BeanieBots

Moderator
I now have all the grounds in the circuit that run off the 5v reg connecting to the line side N ground
That is the exact problem I'm referring to.
According to your diagram 0f 07:20, the clean regulator ground is not used by anything. Your 40X1 for example has its ground connected to the line input ground. The filter does NOTHING.:(

To help get your head around it, consider a snapshot in time.
Take that snapshot at a time when the line ground is 100v less than the regulator's "clean" ground. Then have a look at your circuit and work out what will be going on.
eg the 40X1. Vcc will be at 5v wrt to the regulator ground.
0v will be at -100v wrt to regulator ground.
Hence voltage across 40X1 will be 105V.....
Such a shame when there's a lovely clean 5v available between pins 2 & 3 of the regulator;)

As for resonators. External ones will be more accurate but if you don't have any timing critical fucntions, then internal will save time money & effort.
 
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