Hello all,
I am trying to take a voltage in, then bump it up a bit and then output it. The analogread command does real nice and bringing it in. I just don't know which command to deliver this new voltage that will adjust each time the cycle completes.
Please help,
Thank You
Robert
Robert,
Arduino (technically atmega chips) has no true analog output. The analogWrite command on certain pins are pulse with modulated output. What device is supposed to receive this output?
The computer on my truck. i am trying to modify the 02 sensor voltage. Circuitry can do this, its just bit complex.
Circuitry can do this, its just bit complex.
Only when you use a complex device like a microcontroller to perform a simple function.
I'm really not sure what hardware is appropriate to use in a car application, but a simple op-amp in an non-inverting amplifier configuration will allow you to "bump up" an input voltage. Add a potentiometer for adjustability.
The Voltage Range coming in is 200mV - 800mV or so. I want to add about 200mV to whatever the signal is. I wanted to use a microcontroller, mostly because I've got it doing some other functions, and just thought eliminate the most of the circuitry and let the programming handle it.
If you want to add 200mV, you can use a battery and voltage divider in series with the original output. You are not going to use this output to drive anything, right?
Long story short, unless the signal you are trying to modify is a square wave with the duty cycle indicating the sensors output, you cannot do what you want with just a micro controller. You have to add external hardware. It could be something like a Low pass filter to turn the PWM into a dc voltage, or it could be an op-amp based design, or it could be a DAC.
If you are going to have to add hardware to the micro anyway, you might as well build this circuit without it.
Any reason that you need 200mV on top of your sensor output? May help us making you some suggestions.