Hi all. New to this forum, hopefully I've found the right section.
I'm working on an electronics project and I'm having trouble finding an answer to one particular question. Is there any reason you can't charge a supercapacitor without a charging circuit? I see lots of circuits online that may work, but I'm not sure that I actually need one for my application.
My project is a controller board that takes a PWM input and controls a stepper motor with it. It's designed to be installed in a vehicle, connected to the IGN switched 12V.
The project is functional, but I want to add a function that moves the stepper motor to a certain position when the PWM signal goes to zero (ie. when the vehicle is turned off). This means the Arduino and driver need to be powered momentarily after turning the key from the IGN position. Obviously I don't want to wire the it to constant 12V as it would cause a parasitic draw on the battery.
I was thinking the best thing to do would be to add a 12V supercap across the input power. This way it would charge up whenever the vehicle is running, then on shutting the vehicle off provide a few seconds of power for the stepper to move to it's set position.
Is it as simple as what I'm suggesting, or do I need a circuit to handle this? Is there any difference if I use two 6V supercaps in series with one another (still parallel with the input power), since 6V supercaps seem to be more cost-effective?
Thanks, Chris
I'm working on an electronics project and I'm having trouble finding an answer to one particular question. Is there any reason you can't charge a supercapacitor without a charging circuit? I see lots of circuits online that may work, but I'm not sure that I actually need one for my application.
My project is a controller board that takes a PWM input and controls a stepper motor with it. It's designed to be installed in a vehicle, connected to the IGN switched 12V.
The project is functional, but I want to add a function that moves the stepper motor to a certain position when the PWM signal goes to zero (ie. when the vehicle is turned off). This means the Arduino and driver need to be powered momentarily after turning the key from the IGN position. Obviously I don't want to wire the it to constant 12V as it would cause a parasitic draw on the battery.
I was thinking the best thing to do would be to add a 12V supercap across the input power. This way it would charge up whenever the vehicle is running, then on shutting the vehicle off provide a few seconds of power for the stepper to move to it's set position.
Is it as simple as what I'm suggesting, or do I need a circuit to handle this? Is there any difference if I use two 6V supercaps in series with one another (still parallel with the input power), since 6V supercaps seem to be more cost-effective?
Thanks, Chris