Hello,
I've been stumped by a project because of a lack of understanding. I need to use an Arduino (because it's controlling a lot of other related stuff and has available outputs) to do pulse width modulation on 12VDC. I looked up solid state relays and could not find anything that had a control voltage of 0-5VDC and could switch up to 15VDC. Then i looked up mosfets and found some post showing using n-channel mosfets to do PWM but on smaller voltage. I purchased some n-channel mosfets and when I generate PWM from the Arduino, i get the correct frequency and duty cycle but wrong amplitude. This is using a single mosfet with arduino to signal, 12+ to source, and drain going to +12 side of load and -12 side of load going back to -12 on power supply. I think I have it hooked up wrong, but at the same time, i think the circuit is wrong.
Here is my goal:
Use Arduino 0-5V to generate a PWM signal (done, verified with oscilloscope)
apply that signal to a SSR or circuit that will:
-send a steady +12 volts when the signal (from arduino pin x) is just on (+5VDC)
-send 0VDC when the signal (from arduino pin x) is 0VDC
-PWM on the +12VDC when the signal (from arduino pin x) is PWM (generate the same PWM)
I don't understand circuits enough and its been so many years that I don't remember my options or how to complete this after my first attempt failed. Last night I tried to make a circuit in autodesk eagle free and could not get the mosfet to map so I could simulate the signal and test.
Any ideas on how i can complete this using mosfets? Or if there is a relay I can buy that can be used to send/mirror the 0-5VDC signal on 12VDC?
I've been stumped by a project because of a lack of understanding. I need to use an Arduino (because it's controlling a lot of other related stuff and has available outputs) to do pulse width modulation on 12VDC. I looked up solid state relays and could not find anything that had a control voltage of 0-5VDC and could switch up to 15VDC. Then i looked up mosfets and found some post showing using n-channel mosfets to do PWM but on smaller voltage. I purchased some n-channel mosfets and when I generate PWM from the Arduino, i get the correct frequency and duty cycle but wrong amplitude. This is using a single mosfet with arduino to signal, 12+ to source, and drain going to +12 side of load and -12 side of load going back to -12 on power supply. I think I have it hooked up wrong, but at the same time, i think the circuit is wrong.
Here is my goal:
Use Arduino 0-5V to generate a PWM signal (done, verified with oscilloscope)
apply that signal to a SSR or circuit that will:
-send a steady +12 volts when the signal (from arduino pin x) is just on (+5VDC)
-send 0VDC when the signal (from arduino pin x) is 0VDC
-PWM on the +12VDC when the signal (from arduino pin x) is PWM (generate the same PWM)
I don't understand circuits enough and its been so many years that I don't remember my options or how to complete this after my first attempt failed. Last night I tried to make a circuit in autodesk eagle free and could not get the mosfet to map so I could simulate the signal and test.
Any ideas on how i can complete this using mosfets? Or if there is a relay I can buy that can be used to send/mirror the 0-5VDC signal on 12VDC?