Arduino Nano PI Main Discussion

[lc516]

Ok, great he has it working.
I wasn't sure what the Nano's Voltage levels are.
I didn't have issues with the 7660 on 5V logic.

Did you done the project?

I'm not sure,is the C2 and C3 can provide enough power in a clock cycle on 1K Hz?

[waltr]

Nano I/O output 5v, I can get -5v on TP3 when there are no other components.

The processor is outputting a 5V sync pulse, and the 7660 is operating with a 5V input.
Anyway, I think he has it working now.

Ok, great he has it working.
I wasn't sure what the Nano's Voltage levels are.
I didn't have issues with the 7660 on 5V logic.

[lc516]

Qiaozhi,Thanks for your information.

I used ultimate solustion, I'll open a new PCB make it and add components step by step.
[ATTACH]54941[/ATTACH]

Now,I can get -5v on TP3(ICL7662), I hope that goes well.

continue:

1 I add R1, ok,it's working well, TP3 get -5V.
2 add U3(NE5534P), TP3 get -3.8V
3 Replace with another NE5534P of a different brand, TP3 get -0.6V

I continued to add some components R7 r8 r9 r12, It was no change.

I was upset about the problem....

continue:
test the current of pin5 on 7660, it's 2.8mA.

[Qiaozhi]

What is the logic levels of the 7660 clock coming from the Nano?

In experiments with mu HH2 board I found that a 5V logic clock worked but when using a processor with 3.3V logic the 7660 would not clock. Solution was to use a transistor to level shift to a 12V clock into the 7660.
Maybe this is the issue.

The processor is outputting a 5V sync pulse, and the 7660 is operating with a 5V input.
Anyway, I think he has it working now.

[lc516]

What is the logic levels of the 7660 clock coming from the Nano?

In experiments with mu HH2 board I found that a 5V logic clock worked but when using a processor with 3.3V logic the 7660 would not clock. Solution was to use a transistor to level shift to a 12V clock into the 7660.
Maybe this is the issue.

Nano I/O output 5v, I can get -5v on TP3 when there are no other components.

[waltr]

I think the problem is that you're using an ICL7662 instead of an ICL7660.
Although looking at the ICL7662 datasheet, I cannot see anything which explicitly states that it won't run at 1kHz.

What is the logic levels of the 7660 clock coming from the Nano?

In experiments with mu HH2 board I found that a 5V logic clock worked but when using a processor with 3.3V logic the 7660 would not clock. Solution was to use a transistor to level shift to a 12V clock into the 7660.
Maybe this is the issue.

[lc516]

I think the problem is that you're using an ICL7662 instead of an ICL7660.
Although looking at the ICL7662 datasheet, I cannot see anything which explicitly states that it won't run at 1kHz.

Qiaozhi,Thanks for your information.

I used ultimate solustion, I'll open a new PCB make it and add components step by step.


Now,I can get -5v on TP3(ICL7662), I hope that goes well.

[Qiaozhi]

I use a icl7662cpa replace the abnormal MC7660. But it have same problem, I can't get -5V on TP3 if use 1k external clock.
If use internal clock(disconnect R1) I can get TP6 output, just a lot of noise on there.
Do I should check C3 and C2, or elsewhere?


[ATTACH]54938[/ATTACH]

Any information you can provide, Thank you guys!

I think the problem is that you're using an ICL7662 instead of an ICL7660.
Although looking at the ICL7662 datasheet, I cannot see anything which explicitly states that it won't run at 1kHz.

[Qiaozhi]

Two other MCU's to think about that both have Arduino IDE support.
72MHZ STM32 Blue Pill
600MHz Teensy 4.0

My goal (with the Voodoo) was to convert it to an Arduino platform. I am much better with Arduino's then the supporting electronics. I have always done everything I can to avoid hardware and put as much logic into software as I can. Just some ideas.

I'm currently working on an Arduino Nano-based adapter for the existing Voodoo PCB. The PI channel is working, and I'm just about to implement the DISC channel.
I will post details in the Voodoo thread when completed (Diptrace files, Gerbers, and Arduino sketch).

[lc516]

Two other MCU's to think about that both have Arduino IDE support.
72MHZ STM32 Blue Pill
600MHz Teensy 4.0

My goal (with the Voodoo) was to convert it to an Arduino platform. I am much better with Arduino's then the supporting electronics. I have always done everything I can to avoid hardware and put as much logic into software as I can. Just some ideas.

Maybe you don't need a better MCU on this project, unless If you want to get OPA output through ADC ?
But, the new idea are always good!

[dingbatca]

Two other MCU's to think about that both have Arduino IDE support.
72MHZ STM32 Blue Pill
600MHz Teensy 4.0

My goal (with the Voodoo) was to convert it to an Arduino platform. I am much better with Arduino's then the supporting electronics. I have always done everything I can to avoid hardware and put as much logic into software as I can. Just some ideas.

[lc516]

yes,I think I know what's wrong after excluding other possible problems.
I used a unmatch "MC7660", it can't runing on1k external clock.
I'll buy a new icl7660.


thanks for your information

I use a icl7662cpa replace the abnormal MC7660. But it have same problem, I can't get -5V on TP3 if use 1k external clock.
If use internal clock(disconnect R1) I can get TP6 output, just a lot of noise on there.
Do I should check C3 and C2, or elsewhere?




Any information you can provide, Thank you guys!

[lc516]

You want to synchronize the transmitter to the converter.
This is to avoid the switching transients that might interfere with the receive signal if you were to let the 7660 run on its own. This is covered on page 10 of the book.

Thanks for your reply, That's same as I guess.
I have ordered this book,maybe I can recive it in two weeks. It need to travel half of the earth.

[surfdetector]

Hi,Qiaozhi

I have a question, Why does the 7660 not use internal clock?

You want to synchronize the transmitter to the converter.
This is to avoid the switching transients that might interfere with the receive signal if you were to let the 7660 run on its own. This is covered on page 10 of the book.

[lc516]

Have you programmed the Nano?
You must do that before you can measure -5V at TP3, as the Nano generates the external clock for the 7660.

Hi,Qiaozhi

I have a question, Why does the 7660 not use internal clock?