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How do I dim a PWM input with a POT

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cdelicath

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I have a driver for high power LED's that uses PWM 0 to 5v to dim the LED's. This works great when using the Arduino to control dimming but what if I want to dim the driver manually with a 10k POT or otherwise?
Please be kind I am a big old Noob.
 
You can generate a pot-controlled PWM signal with a 555. Just Google 555 PWM circuit.
 
I thought a 555 was used to dim PWM.
I am looking for a way to convert the driver I already have that uses PWM 0 to 5v to dim but via a pot manually. I apologize if I am missing something here. Could I just supply +5 to one end of a pot and the other to the PWM pin in the driver and then adjust it that way?
 
I think I grasp what you're asking and what you're working with. If I'm correct in my thinking then no you cannot simply attach a POT to the drivers PWM input and have it properly (I'm guessing it would just stay at 100% brightness). You need something that generates a PWM signal with a POT control. A 555 timer as stated above can be used for this purpose and is very simple to get up and running. **broken link removed** simliar to the linked page but instead connect the motor control line to your LED driver's PWM input.
 
Ok so I looked at the link and I understand now that what I need now is a PWM signal and not a limiting of V to dim. Forgive me for even asking because I don't want to sound lazy but is there any way you could explain more about the 555 chip and how I would go about connecting a POT to it to make it dim. Trigger, output and control explanations are all a bit overwhelming for my level of understanding. It would be a great help to understand in lemans terms how this thing works.

**broken link removed** I would like to dim this via a POT
 
The schematic in jimlovell777's reference has a PWM schematic with a pot to control the duty-cycle. Just build that.
 
Do you want to dim the LED's, by moving the potenciometer? if you are using an arduino i can help you.
 
well I am using a arduino to dim these but I also want the ability to dim via the POT for the time being while I try to figure out the code for the arduino. I have the dimming working with the arduino but now I need to figure out how to add my RTC and use it to have the LED's dim at a set time.
 
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for dimming with the POT, the arduino IDE has an example, as for the RTC, wich one are you using?
 
I am using the DS1307 For my RTC I had it working at one time but I moved to a I2C LCD board to save pins on the arduino and I am trying to figure that thing out now just so I can print out time and date on the LCD.
I am looking for a separate way to dim these drivers via a analog dial completely separate from the arduino.
I understand that I need to build a 555 timer to do what I am looking for but my schematic reading skills are really crappy. I need someone to draw me a fricken map:D
I have been searching for a picture of one online so I can see where the wires go but no luck yet.
I would love to learn more about coding on the arduino. Any recommendations on beginners learning from the ground up? I am a web developer so I was thinking I would take to programming a bit easier but I was very mistaken.
 
Can any one explain to me what's going on here?
**broken link removed**
I recognize some of the symbols but i'm lost on the rest.
 
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