Hi,
I am wondering if the 16-channel PWM/Servo Shield can be used to drive 16 water/air solenoids instead of servos. The solenoids I have in mind are these DC 12V ones https://www.ebay.co.uk/itm/252510150316.
Sorry about the noob question, but still quite new to arduinos and electrical engineering.
16-channel PWM/Servo Shield for 12V water/air solenoids?
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- gjnn
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- adafruit_support_bill
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Re: 16-channel PWM/Servo Shield for 12V water/air solenoids?
Not directly. They need 160mA at 12v. The PWM pins on the shield will only do about 20mA @5v. You would need a transistor on each channel to switch the current - plus a diode to protect against the kickback from the solenoid.
https://learn.adafruit.com/transistors- ... -2998941-9
https://learn.adafruit.com/transistors- ... -2998941-9
- gjnn
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Re: 16-channel PWM/Servo Shield for 12V water/air solenoids?
Thanks for the help! Do you possibly know if there exists another shield with transistors, that can handle multiple solenoids?
Thanks again!
Thanks again!
- adafruit_support_bill
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Re: 16-channel PWM/Servo Shield for 12V water/air solenoids?
You could use a pair of motor shields: https://www.adafruit.com/product/1438
That shield is based on the same PCA9685 chip as the PWM Servo shield - but with the PWM outputs routed to 4 H-Bridge motor drivers.
The output of each H-bridge is basically equivalent to 2 transistor drivers. So you could control two valves per bridge. That gives you 8 solenoids per shield and the shields are stackable.
That shield is based on the same PCA9685 chip as the PWM Servo shield - but with the PWM outputs routed to 4 H-Bridge motor drivers.
The output of each H-bridge is basically equivalent to 2 transistor drivers. So you could control two valves per bridge. That gives you 8 solenoids per shield and the shields are stackable.
- gjnn
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Re: 16-channel PWM/Servo Shield for 12V water/air solenoids?
Thanks a lot! Might come back later with more specific questions once I've done more reading for the specific project I have in mind!
- gjnn
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Re: 16-channel PWM/Servo Shield for 12V water/air solenoids?
Just to be perfectly clear: if I stack 3 shields, I will be able to have access to 8 x 3 = 24 solenoids in total right? I am asking since I was reading this post https://learn.adafruit.com/adafruit-mot ... ng-shields where it says "Note that stacking shields does not increase the servo connections - those are hard-wired to the Arduino digital 9 & 10 pins."
- adafruit_support_bill
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Re: 16-channel PWM/Servo Shield for 12V water/air solenoids?
Correct. You would be connecting your solenoids to the motor channels - not the servo channels.ust to be perfectly clear: if I stack 3 shields, I will be able to have access to 8 x 3 = 24 solenoids in total right?
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