The Nano breakout board with 2A switched mode 5V regulator is a neat little device, but it has been giving me strange results from the analogue to digital converter.
By Julian
Youtuber, shed dweller, solar charge controller aficionado
where can i get the variable resistor board you have there?
Nice simple fix to a stupid design flaw I think. 🙂
I have a couple of thoughts. If you did use the switch mode supply for the sensor, can you make use of the arduino's external analogue ref pin? Also, would putting a small capacitor between the analogue input pin and ground help reduce the noise?
I've never tried doing that so I don't know if it would definitely help or not. 🙂
Interesting. Perhaps formery it was intendet to be used for another reason and not form measurements.
But could you lower the microfone sensitivity a bit? It's really clipped and hurts even when I lower the video volume.
depending on how accurate, and how responsive you want things to be, you could also stabilize the noise by averaging out a number of subsequent sample values. It's even easy to keep a running average going at the same speed as the samples, just averaged over the last X read values.
It sounds like you've tried filtering the analogue I/P without much success. It could be that the board (now) has poor grounding. You really need to keep the two supplies (one is your LED power, the other your measurement system – sensor/ADC) separate. If you have relatively high current flowing in the measurement ground this could cause ground bounce which will mess the measurement up.
Why didn't you link the +5V from the switch mode power supply to the AREF pin on the arduino, so it would be comparing the analog signals with the voltage coming out of your extension board.
[EDIT] Oh, someone else mentioned this before…
30.04.14
I was writing to you almost two months ago, and you answer me very fast. Thank you. After that I was waiting for LED and booster to arrive from the China. Two weeks ago I started experimenting with LED 100 W.
According to information from the internet, main problem with 100W LED chip is how to cool it down. High bay lamp has a passive, very big aluminum heat sink ( ~ 2 kg ). Because expensive transport cost from China, I made it by myself. It work fine, and after 1 Hour working, temperature around Led chip was lover than 50 C. I was using LED Power Supply Driver 100W For 100Watt High power LED Light Lamp Bulb 85-265V.
My first intention was to make led lamp for night fishing, so it should work with battery 12 V, like you show it in your YouTube video. I ordered DC-DC 400W 6-40V to 8v-80v 10A Boost Converter Step-up Module Power Supply CC CV.
I connect Boost converter to my car battery ( 12 V, 45 Ah ). Dc-dc boost converter has output about 32 V and 3 A.
After about 1 hour. led lamp turns off. Heat Sink Temperature, near Led chip, was less than 50 C. After that I connect LED to LED Power Supply Driver 100W For 100Watt High power LED Light Lamp Bulb 85-265V, and it works fine.
Probably problem is the car battery. I didn’t realize that bust converter will not use 3 A, from the car battery. I didn’t measure that, but I think that it’s about 8-12 A because of losses.
I need it to work 3-4 hours on 12 V.
Can you help me with some advice. How many Amps booster is using from the battery?
Should the solution will bee the AGM Battery for the golf electric car?
Thank you
Bila Milos
Nice presentation again Julian… throws me way back to my AD/DA days…
Why you would like to have the 6 analog pins connected to the switch mode power supply would be if your sensors need a bit more current than your pot.
You probably could have checked if the sensor board has the switched 5V connected to the analog reference (there is even a pin for this). If not then this would be an option plus adding big cap to the switch output.
I really like this project! Can you tell me the library you are using to display txt on the max 7219 modules? Thanks!
It would be great if you could put eBay links for all the modules used in the video. I know that the micro & breakout board linked were listed in video #1, but the LED matrix, driver board and potentiometer board are also of interest!
Yep. Digital supply to analog input pins is a design error for this board. You may also find that the analog mux for the A/D is slightly interferred with by whatever voltage in on the analog input last scanned before this one.
Using the switch mode regulator power for measurement and a different one for reference will make the voltage fluctuations on both power supply add up that is why you see more noise.
Of course you can add a digital filler in software to make the reading even more stable. A basic filter will be just to take 5 to 10 measurements and calculate the average that average will then be displayed.