I designed a PCB using Eagle to build your micro-current device using SMD resistors for my own use.

It would be awesome to share that here if you don't mind.

In double-checking against the schematic and the board point-to-point wiring in this thread I found one more discrepancy.
The wires from U3 "0" and "2" go through the 270K resistors to the 3K resistor and IN+ in the Schematic.
In the board wiring, the wiring from U3 "0" and "2" go to the 3K resistors and then though the 270K resistor to IN+.
I assume the Board wiring is the correct circuit......right?

Nice catch! Thanks for pointing it out. The schematic and the simulation is correct. It looks like I chose to use 3K resistors instead of the 10K in the simulation, but otherwise it's the reference. Looks like I put the wires from the 4017 to the op-amps in the wrong place on the drawing of the board. That's really disturbing but doo-doo happens. I wonder if anyone built one of these?

The corrected drawing is in post #26.

By the way, your circuit design is very creative - thanks!

Thanks!

 

Did you mean to post this here, or over in the "random noise below 30Hz) thread?

Sorry, I was distracted in the middle of looking here at your link over there. But I can't find the "random noise …" thread anymore.

 

Hey Wayneh
Just saw your post on your electro-stimulation device. Was comparing it to some CES circuits I found some years back. Since then this same person added circuitry on TES. (CES - Cranial Electro Stimulation, TES - Trans-cranial Electro Stimulation)

In case you are interested in them they can be found HERE. When on the site, select "Wetware_PDF" and "WetWare_Zip" look for CES & TES.
There are several circuits and some that use Tiny13, 25 uC's.

 

Hey Wayneh
Just saw your post on your electro-stimulation device. Was comparing it to some CES circuits I found some years back. Since then this same person added circuitry on TES. (CES - Cranial Electro Stimulation, TES - Trans-cranial Electro Stimulation)

In case you are interested in them they can be found HERE. When on the site, select "Wetware_PDF" and "WetWare_Zip" look for CES & TES.
There are several circuits and some that use Tiny13, 25 uC's.

Did you mean to provide a link?

 

It looks like I chose to use 3K resistors instead of the 10K in the simulation, but otherwise it's the reference.

I've reminded myself that the 3K resistors in my build set the minimum resistance the user can choose. They're in series with a ganged 10K pot, and the maximum resistance is thus 13K for each, which produces about 900µA as a maximum treatment current.

 

Did you mean to provide a link?

Indeed I did!

http://ullasmann.eu/

 

Dear @wayneh
Greetings
Kindly let me to know the out put frequency of you micro-current unit. Is the frequency is 0.5Hz at bipolar micro-current which is <500 micro Amphere please

 

Dear Wayneh,
greetings
The provision at the power and adjustable out put in the circuit is confusing me a lot, because I am a novice to this field. If it is permissible and possible kindly let me to know clearly these circuit part please

 

I just noticed that the last time Wayneh was seen here was about two months ago. Other members who know the answer to dheena0104's question should not stand on ceremony if they can help now.

 

I just noticed that the last time Wayneh was seen here was about two months ago. Other members who know the answer to dheena0104's question should not stand on ceremony if they can help now.

According to this, he was last seen yesterday evening:

 

In that case, stand as you please

I suspect things will be better after my eye surgery next month.

 

I suspect things will be better after my eye surgery next month.

Hope it goes well. I'll probably have to have some cataracts removed sometime in the next couple of years, am not looking forward to it...

 

Hope it goes well. I'll probably have to have some cataracts removed sometime in the next couple of years, am not looking forward to it...

At least you can look forward to better eyesight ...

 

Dear Wayneh,
Greetings
After repeated reading of the circuit description provided below the circuit diagram under post#1, I am able to come to a conclusion that R8 (load) is body resistance (load body part). Because, out put connection of the dual pot (R10 and R11) is shown as an open end (dual pot pin 1, 1), I got confused.

The open end of dual pot pin has to be connected to negative terminal of the battery. Next is regarding the switch at the adjust out put dual pot. Is this switch in necessary? If this switch is for dual pot disconnection/connection, then when disconnected, how R10 and R11 (3 ohms each) will get connected to negative power terminal.

Finally, kindly permit me to have clarification regarding the dual pot provision at the in put power supply (6-12 V DC) please. Missed resistance order (R9 and R15) is observed in the circuit diagram and PCB component figure please.

 

@wayneh

Dear learned members
Greetings
Kindly permit me to have the circuit diagram of the corrected micro-current unit, which was shown in post 28 please

 

@wayneh

Dear learned members
Greetings
Kindly permit me to have the circuit diagram of the corrected micro-current unit, which was shown in post 28 please

Sorry @dheena0104 for the slow response. I've been taking a hiatus and just checked in today to find an old post of mine. I noticed an unread email and saw that @DickCappels had made that extra effort to catch my attention. It worked, and you can thank Dick for that.

Can you clearly restate your remaining questions? I'll do what I can to answer them but I don't want to waste your time and mine answering questions you'r not asking.

The correction made in #28 was to the diagram of the layout. As I commented in #61, the original schematic and the simulation based on it were correct. I just flubbed the layout drawing and had to correct it when a kind user pointed it out.

 

Hope it goes well. I'll probably have to have some cataracts removed sometime in the next couple of years, am not looking forward to it...

I’ve had cataract surgery on both eyes. No issues and my sight was greatly improved after a few days. When my bandage was removed, I could see color and detail as if I was in my 20s.

 

I’ve had cataract surgery on both eyes. No issues and my sight was greatly improved after a few days. When my bandage was removed, I could see color and detail as if I was in my 20s.

Thanks, that's what I'm hoping for!

 

Sorry @dheena0104 for the slow response. I've been taking a hiatus and just checked in today to find an old post of mine. I noticed an unread email and saw that @DickCappels had made that extra effort to catch my attention. It worked, and you can thank Dick for that.

Can you clearly restate your remaining questions? I'll do what I can to answer them but I don't want to waste your time and mine answering questions you'r not asking.

The correction made in #28 was to the diagram of the layout. As I commented in #61, the original schematic and the simulation based on it were correct. I just flubbed the layout drawing and had to correct it when a kind user pointed it out.

Dear Wayneh,
Greetings
Thank you for the kind reply and at the same time I request you to kindly bare with my novice questions. These are not questions but a request for clarification please.
The open end of dual pot pin has to be connected to negative terminal of the battery. Next is regarding the switch at the adjust out put dual pot. Is this switch in necessary? If this switch is for dual pot disconnection/connection, then when disconnected, how R10 and R11 (3 ohms each) will get connected to negative power terminal.
Finally, kindly permit me to have clarification regarding the dual pot provision at the in put power supply (6-12 V DC) please. Missed resistance order (R9 and R15) is observed in the circuit diagram and PCB component figure please.
Started assembling the unit. Waiting for TLV272; Ordered through tanotis India
Sorry for the disturbance please

 

The open end of dual pot pin has to be connected to negative terminal of the battery.

Yes, I showed that in one part of the drawing but apparently I left off the ground connection details in at least one of the drawings. Sorry for the confusion.

Next is regarding the switch at the adjust out put dual pot. Is this switch in necessary? If this switch is for dual pot disconnection/connection, then when disconnected, how R10 and R11 (3 ohms each) will get connected to negative power terminal.

Necessary? No, you could do without it and use a separate power switch. But I had to buy the dual-gang pot anyway and the cost is essentially the same if you get a switch built into it.

Finally, kindly permit me to have clarification regarding the dual pot provision at the in put power supply (6-12 V DC) please. Missed resistance order (R9 and R15) is observed in the circuit diagram and PCB component figure please.

There is only one dual-gang pot. The built-in switch is used to switch the power while the variable resistors are for the output adjustment. It appears twice in the drawings, for clarity, but it's the same device.

A gap in the resistor numbers happens naturally in LTspice - it labels each resistor sequentially - when you delete a resistor and do not edit the remaining numbers. I was too lazy to make sure there was no gap.