Me and my brother are working on a project together and I was hoping for some advice. While I am familiar with some electronic babble, my experience is pretty much exclusively with LEDS... To say I am out of my comfort zone is a light way of putting it lol
But we are doing this project to learn, and learn I shall!
Basically the project is some fans partially controlled with a PIR(motion senser). The fans are always on at the "low" speed, but when the motion senser detects movement the fans turn on high for a amount of time before turning back to low afterwards. Rinse and repeat.
The motion senser I was planning on using was https://www.adafruit.com/products/189
It runs on 5V-12V power, Digital signal output is 3.3V high/low.
The fans are these https://www.amazon.com/F12-PWM-PST-...&qid=1481148700&sr=8-1&keywords=arctic+5+pack
Voltage: 0.25A / +12V
They can be daisy chained together and are PWM controlled if need be. I plan on running 2 fans with this project. These fans can run on as low as 5 volts (I double checked)
For the microcontroler I was planning on using the ADAfruit trinket https://www.adafruit.com/product/1500 (the 5V one)
As for the power supply we where planning on using a 12V adapter we had laying around.
My current plan is to have the fans power connected to the USB + Output pin and having them run on a base voltage of 5 volts at 500mA (the low speed). the PIR power will connect to the trinket power regulator output pin which supply 5 volts at 150mA. Ground wires go to ground pin. the PIR digital output would connect to the fans so when its triggered it will supply the fans a extra 3 volts of power(the higher speed). I can adjust the timer using the potentiometer that comes on the PIR senser all the way up so it lasts about 4 minutes when triggered. The trinkets power will be supplied by the 12 volt wall adapter.
My main problem is will this even work? Will connecting the 3 volt PIR digital output to the wire that's already supplying the base voltage of 5 volts actually increase it to 8 volts? Will it cause some-sort of feedback and burn out the trinket? In my mind I don't see any issues but I simply don't know enough on the subject to know what I don't know!
My second problem is; Do I even need the trinket? The original plan my brother and I came up with was to control the speed of the fans using PWM and a bit of code to control the timing, but that was before I found out the PIR had a potentiometer. At this point it seems like I am using the trinket as a voltage regulator, not a micro-controller. Should I find a voltage regulator instead? What would you suggest?
My third problem is the fans low speed would be 5 volts and their high is only 8 volts. Not much of a improvement. I'm thinking about upping that to 12 volts via a step-up booster. But do they even make step up boosters that go from 3 volts to 7 volts? I know these particular fans work at 5 volts, so that's not an issue.
Lastly; Is there a better way to do this?
Thank you in advance for reading my woes, and any advice you have is appreciated.
But we are doing this project to learn, and learn I shall!
Basically the project is some fans partially controlled with a PIR(motion senser). The fans are always on at the "low" speed, but when the motion senser detects movement the fans turn on high for a amount of time before turning back to low afterwards. Rinse and repeat.
The motion senser I was planning on using was https://www.adafruit.com/products/189
It runs on 5V-12V power, Digital signal output is 3.3V high/low.
The fans are these https://www.amazon.com/F12-PWM-PST-...&qid=1481148700&sr=8-1&keywords=arctic+5+pack
Voltage: 0.25A / +12V
They can be daisy chained together and are PWM controlled if need be. I plan on running 2 fans with this project. These fans can run on as low as 5 volts (I double checked)
For the microcontroler I was planning on using the ADAfruit trinket https://www.adafruit.com/product/1500 (the 5V one)
As for the power supply we where planning on using a 12V adapter we had laying around.
My current plan is to have the fans power connected to the USB + Output pin and having them run on a base voltage of 5 volts at 500mA (the low speed). the PIR power will connect to the trinket power regulator output pin which supply 5 volts at 150mA. Ground wires go to ground pin. the PIR digital output would connect to the fans so when its triggered it will supply the fans a extra 3 volts of power(the higher speed). I can adjust the timer using the potentiometer that comes on the PIR senser all the way up so it lasts about 4 minutes when triggered. The trinkets power will be supplied by the 12 volt wall adapter.
My main problem is will this even work? Will connecting the 3 volt PIR digital output to the wire that's already supplying the base voltage of 5 volts actually increase it to 8 volts? Will it cause some-sort of feedback and burn out the trinket? In my mind I don't see any issues but I simply don't know enough on the subject to know what I don't know!
My second problem is; Do I even need the trinket? The original plan my brother and I came up with was to control the speed of the fans using PWM and a bit of code to control the timing, but that was before I found out the PIR had a potentiometer. At this point it seems like I am using the trinket as a voltage regulator, not a micro-controller. Should I find a voltage regulator instead? What would you suggest?
My third problem is the fans low speed would be 5 volts and their high is only 8 volts. Not much of a improvement. I'm thinking about upping that to 12 volts via a step-up booster. But do they even make step up boosters that go from 3 volts to 7 volts? I know these particular fans work at 5 volts, so that's not an issue.
Lastly; Is there a better way to do this?
Thank you in advance for reading my woes, and any advice you have is appreciated.
