Timeline for Can I control LED brightness with potentiometer without any code, as well as reading the potentiometer value?
Current License: CC BY-SA 4.0
10 events
| when toggle format | what | by | license | comment | |
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| Nov 6, 2020 at 12:41 | comment | added | HectorBart | @Majenko Thanks, I have ordered a few of them so I will report back here once I get it working. | |
| Nov 5, 2020 at 22:26 | comment | added | Majenko | A dual gang pot will work fine, but if you don't want to use one (or can't get hold of one of the right type) then a buffer is the way to go. | |
| Nov 5, 2020 at 20:53 | comment | added | HectorBart | @Majenko Thanks for this explanation, I will read up on op-amps as I have not come across them before. Does this mean jsotola's suggestion of using dual gang pots not work? I am not all that familiar with analogue electronics, so forgive me if I have misunderstood something. | |
| Nov 5, 2020 at 0:21 | comment | added | Duncan C | Yeah, that part I get. | |
| Nov 5, 2020 at 0:21 | comment | added | Majenko | The resistor basically converts the voltage into a predictable current through ohms law. | |
| Nov 5, 2020 at 0:20 | comment | added | Duncan C | And then the current limiting resistor lets more or less current though based on the input voltage, thus varying the brightness of the LED. I like it. | |
| Nov 5, 2020 at 0:19 | comment | added | Majenko | Basically, yes. The potentiometer is just a reference for the opamp to create it's own output with lower impedance. | |
| Nov 5, 2020 at 0:19 | comment | added | Duncan C | It's worth noting that you want to be sure to use a linear pot. A log pot would give very squirrelly results. | |
| Nov 5, 2020 at 0:17 | comment | added | Duncan C | So you're using an op-amp to create a "stiff" variable voltage from the voltage divider so the load of the LED doesn't affect the ADC reading? I wish my analog electronics chops were stronger. | |
| Nov 4, 2020 at 22:47 | history | answered | Majenko | CC BY-SA 4.0 |