Reading 5 analog sensors, with one ADC pin, would this circuit work?

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1

well, as usually I have all ADC pins used up on my arduino, 2 of them are used by i2c, and the other 4 are used, 3 for line follower, and one for sharp sensor at the front.

 

I need more proximity sensors, and a new line follower with 5 qrd1114 instead of 3, for maze solving.

So would this work?

 

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Consider the 555 and 4017 properly wired, and nvm the missing resistor with the opto isolators, couldn't bother :-P

basically the 555 clock the 4017, and that "opens" different QRD readings, the arduino gets synchronised and reads them...

 

At first i was going to use a digital pin to clock the 4017, but that would give me timing issues with other devices(i think) so i decided to clock it with a 555.

 

This works in theory... at least my theory, lol

 

Waiting for the opto isolators, and will try.

 

Any other ways of reading lot's of analogue signals with only one ADC pin?

 

thanks.

 

 

 

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Did you know the QTR-8RC

Did you know the QTR-8RC from Pololu. This a a very easy way to use digital inputs instead of analog. The trick is to use a capacitor instead of a resistor between VCC and collector of the foto transistor, to get a quasi digital signal out of an analog sensor.

I have succesfully connected this device with an I2C port expander (PCF8574). Works great as a line follower. And it is faster than reading multiple analog sensors. If you need an exact analog value this method will not work, but for a line sensor its ok.

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could use something like

could use something like this.

http://www.national.com/mpf/DC/ADC0838.html

they also have 0831, 0834 and some others…