yes, and it still works now. Only with two chips though. the same two chips which have always worked. I can't get any other chips to work with my circuit.

 

So how many 4011 have you fried?

First 4 from Maplin and 2 were fried and 2 working. Then 18 from eBay and all fried. The eBay seller promised to give you another 36, so make sure you dont fry them again...

I normally buy 4011 from Element 14 and they are either ST or Motorola brands. I have diagnosed faulty 4011 from Yamaha Electones models like FC10 and the B-x06 models. But in normal usage I think they are quite robust and not so easy to die. Might be due to the high humidity in the place I live.

Allen

 

I'm in the belief that I've not personally fried any.

I've been very careful with them all.

In fact, the only two that have ever worked, I purposely treated with less respect, on purpose, to test the theory that I might be the cause. They are still fine and working, despite being plugged in and unplugged from my breadboard and circuit on numerous occasions now.

I don't believe im at fault here.

 

Just been talking to the eBay seller on the phone. Sounds a lovely guy. Genuine. He's going to try and help me, no matter what, with this issue.

He's sending me out a batch of new chips, and he's happy to discuss in the new year how I get on etc.

Fingers crossed. Let's see.

 

Isn't too weird that you get so many non-working ICs from different vendors?

Your circuit where one 9V regulators is pulsed at the input makes me doubt of the rest. And those diodes in series at the input of all of those "MOSFETs"...!

No matter how reasonable (or not) it could be, how did you actually implemented such a circuit?

Sorry but too many unusual things. . . at least for me.

 

Might be due to the high humidity in the place I live.

Allen

Yes. Every time we crossed the area, quite close to your country, weather was humid and mostly hot.

 

I'm working on a wooden table. Here is a portion of my circuit containing the NAND's. Obviously i'm using this circuit twice, and they are only connected to one another by utilising the same power source. The LTSpice circuit doesn't show the power source, but this is done as the same way as these inputs is, using a 7809.

The other major difference is that i'm using a BC548B in place of the BC847C (couldn't find a model of it, so used the next closest equivalent)

As I say, the circuit is working and doing what i want it to do, but ONLY on one circuit with the two NAND chips that are actually working...!? The other half wont work with another other chips, but will work with the two i have working, when i swap them over to that side.

So, if this isn't the real circuit you should post the real one. If it is. What powers the IC's??

 

Is the load on the VRegs really just the input of a 4011? Maybe we should just offer you some "contrived" advice. Please post a real schematic or stop this, now.

 

I found my problem.

One of my "good chips" is different from all the others. It's rogue for whatever reason...?!

Pin 1 going into a floating state (neither grounded or 12v applied) still allows the output from gate one to go high instead of waiting for me to ground it down to 0V.
With all the others, the output goes low in this floating state.

Now I can't understand why my circuit isn't working with legitimately working chips?! For whatever reason, it's only working when this rogue chip is included.

I give up. I'll put up my real circuit for people to see. I clearly need help with this, despite being 95% there myself...

 

This is my circuit.

When the side lights are off. So are the Orange LED markers.
When the side lights are on. So are the Orange LED markers.
When the side lights are off, and then the indicator is on, then the appropriate side Orange LED marker flashes in time with the Indicator until indicating is cancelled and then returns to the off state.
When the side lights are on, and then the indicator is on too, then the side light request to the appropriate Orange LED is overridden by the indicator request, causing it to flash in time with the Indicator until indicating is cancelled, and then returns to the on state.

The pulse converters seem to be the only parts of the circuitry which are working. The 4011 element of the circuit(s) only seem to work with this one rogue chip, as described above....!? why? I need help to fix this. Please.

 

...I should say of course, for the above message. It *should* do this that and the other thing.

When the chips don't have the rogue chip in there, then for whatever reason, the side light request is completely ignored. Only the indicating element of the functionality works. If i touch pin 1 with my hand, (holding something metal), then the side light functionality works too.
With my rogue chip in place as one of the chips, then that pair of chips works fine for all functionality as described above...!?

 

@Rissy,

Please send me a list of sellers that you purchase ICs from. I am very cautios when purchasing parts for the very reason that they may be fake or damaged. I have even had dodgy parts from reputable sellers!

Also here is something for everyone to have a chuckel on:

I purchased 50 555Ic's once from a reputable supplier on ebay. But what arrived was polysterine wrapped in foil with the parts pushed in. This would normally be OK if there is ALOT of thick foil but this was the thinnest foil you could find with only one wrap and half the pins where left unconnected. I had to throw them away because I could not risk one of these devices failing

555 ics are not sensitive very much.

I'm keeping all the large ics I'm selling in plain plastic drawers then usually wrap with tin foil. Also I use antistatic bags sometimes.

The warehouse is metal frame, no carpets, humidity is high. There's no static in the first place.

Getting very few claims of defective ics and I sold 1000s. This is from old ics which already were defective.

 

...although, even once i CAN report, i'm sure i'll still be confused. Because as i said, although the other remaining chips wouldn't work on my circuit, they did mostly check out ok using a multimeter on some breadboard with 12V shoved up their arse.

We dont need exaggeration of this kind on the forum.

 

We dont need exaggeration of this kind on the forum.

Yes I know. I'm sorry. I've just been very frustrated with this project over the past few weeks.

 

555 ics are not sensitive very much.

I'm keeping all the large ics I'm selling in plain plastic drawers then usually wrap with tin foil. Also I use antistatic bags sometimes.

The warehouse is metal frame, no carpets, humidity is high. There's no static in the first place.

Getting very few claims of defective ics and I sold 1000s. This is from old ics which already were defective.

Your right about 555 chips not being very sensitive to static however they are still prone to static damage. There is no harm in making sure that all components are stored correctly. I have sold many hundreds of kits with zero reports on failed chips.

Storing chips in plastic draws can be potentially harmful because any static build that occurs is not being properly removed. And sending chips in a tin foil package is really poor practice especially when conductive foam is so cheap.

It costs around 40P for me to take a standard draw and lay a piece of high density static foam inside so that any chips under storage are protected from static discharge. Tin foil never guarantees protection and as shown by Dave Jones anti-static bags dont always work.

@Rissy please do let me know of the suppliers! Also, care to show us a test jig for the failed parts? For example, have a breadboard with pull down resistors on each input, a decoupling capacitor and LED outputs.

One thing that comes to mind is how they are used in the project. If you get certain types of family (for example, 74LS range), they have very specific operational requirements. In one of my projects I needed a 7474 dual flip flop. The circuit never worked until I realised that my chip was a 74LS74 instead of a 74HC74. The difference being the input stage on these chips which results in many problems in a glue logic circuit.

 

This is my circuit.

When the side lights are off. So are the Orange LED markers.
When the side lights are on. So are the Orange LED markers.
When the side lights are off, and then the indicator is on, then the appropriate side Orange LED marker flashes in time with the Indicator until indicating is cancelled and then returns to the off state.
When the side lights are on, and then the indicator is on too, then the side light request to the appropriate Orange LED is overridden by the indicator request, causing it to flash in time with the Indicator until indicating is cancelled, and then returns to the on state.

The pulse converters seem to be the only parts of the circuitry which are working. The 4011 element of the circuit(s) only seem to work with this one rogue chip, as described above....!? why? I need help to fix this. Please.

I don't understand your reasoning for using the 7809s. With only a CMOS input for a load that is below recommended specs for a 1 Amp regulator. Even for a 78L09 (100 mA) regulator.
Maybe just a simple transistor with a pullup to 9 V.
Would a single 78L09 power this circuit?

 

No it wouldn't. I need to regulate all the inputs to the logic to the same level as VDD. So, side lights and indicator (pulse and constant separately)

The reason I picked 9v is because an automotive environment can swing between 10.5v - 14v depending on whether the engine is running or not etc.

 

No it wouldn't. I need to regulate all the inputs to the logic to the same level as VDD. So, side lights and indicator (pulse and constant separately)

The reason I picked 9v is because an automotive environment can swing between 10.5v - 14v depending on whether the engine is running or not etc.

If you say so,
Pulse converter circuit outputs pull up but no pull down resistor?

 

No it wouldn't. I need to regulate all the inputs to the logic to the same level as VDD. So, side lights and indicator (pulse and constant separately)

The reason I picked 9v is because an automotive environment can swing between 10.5v - 14v depending on whether the engine is running or not etc.

So that's a problem...because drop out for the regulator is 2v (like I mentioned in a previous post). This means the voltage into the regulator must be higher than 11v.

Really...you should use one regulator. Maybe an LM7805 or adjustable LM317.

 

Does this truth table summarize the logic for one Side Marker ?

IN | IN | OUT
====================
SL | IND | SM
====================
0 |x |0
1 |x |1

0 |0 |0
1 |0 |1
0 |1 |F
1 |1| F

x=don't care
F= Flash
SL=Side Lamp
IND=Indicator
SM=Side Marker