Hi!
I am currently making an Arduino-controlled 12V Plastic Solenoid Valve circuit based from:
www.martyncurrey.com/controlling-a-solenoid-valve-from-an-arduino-updated/
There are no TIP120 transistors available however in our local electronic shops, only TIP122. Is it possible to make a voltage regulator counterpart of TIP120 using TIP122? If so what other components do I have to change?
The ancient TIP12x series should be avoided for use at 12 volts due to the high voltage drop of a Darlington. Might get away with it at 24 volts but they’re not so good at lower voltages. Your best choice is a mosfet but not per that blog, lots of bad information there, like the choice of IRFZ44. The Internet is full of crap and you’ve found a good example of it.
What are the specs of your solenoid (current required) and which Arduino?
I am currently using an Arduino UNO but I plan on changing it later to ESP32 since I am also making an android companion app.
The specifications of the plastic solenoid valve are as follows:
1/2″ Nominal NPS
Working Pressure: 0.02 Mpa – 0.8 Mpa
Working Temperature: 1 ℃ – 75 ℃
Voltage: 6VDC to 12VDC
Fetched from: https://www.makerlab-electronics.com/product/plastic-water-solenoid-valve-12v-1-2-nps/
fadlawan:
There are no TIP120 transistors available however in our local electronic shops, only TIP122. Is it possible to make a voltage regulator counterpart of TIP120 using TIP122? If so what other components do I have to change?
According to the datasheet, which you should read, the only difference is the CE breakdown voltage; so the substitution is okay.
Just make sure that the solenoid pick-up voltage is low enough that the saturation voltage won't be an issue.
Use a MOSFET. Logic level type, one that can comfortably handle the current your solenoid takes. Forget about the old Darlingtons.
If you want to use an ESP later make sure it switches properly at 3.3V.