Hi. I have a internal reference turned on in one of my analog inputs but I need to read another analog input.
Could I apply 5v once I'm using internal 1.1v referfence ?
I don't need to measure the voltage just "has voltage yes or no".
I'm using Atmega328-PU
tks a lot
No problem, even when using the internal 1.1vdc reference the pin's electrical safety ratings still apply, 0 vdc to chip's Vcc. Of course any voltage above +1.1vdc will return a 1023 counts from the analogRead() function.
Perfect! thats whats I was expecting!! tks a lot!
Just a question..
Could I use the pull down function to get the pin 0v when no incomming voltage or I will put a resistor connected to the GND?
Any idea?
cabecinhas:
Just a question..
Could I use the pull down function to get the pin 0v when no incomming voltage or I will put a resistor connected to the GND?
Any idea?
There is no internal pull-down option available on the chip, only a pull-up, so you would require an external resistor for that.
Lefty
Could I use the pull down function to get the pin 0v when no incomming voltage or I will put a resistor connected to the GND?
Depending on what you need to accomplish & if you have a spare pin on the uC, you can connect a pull-down between Analog(x) and another digital pin, say D5 as an example. Put D5 into input mode for a HighZ where the resistor is imposing no (very, very light) load on the Analogx. Put D5 into output mode to pull-up to 5V or pull-down to Gnd (less the Vdrop across the internal CMOS gate.)
Ray