Multiple analog inputs for reading IR-photodiodes

Other Hardware Sensors
1

Hi,

I have a question about using multiple analog INPUTs on my Arduino Uno.

I want to read the data from 20 IR-photodiodes, but the arduino only got a few analog pins. Is there something like the 74HC595 shiftregister, but in reverse? And compatible with analog data.

I've found the 4051 Multiplexer. Can I use this for my project? Or does someone have a little example of how to use the 4051 Multiplexer for reading analog data.

Thanks!

2

I think maybe you can do this:

You divide the analog inputs into 4 sets, and use digital pins to switch each set sequentially and simultaneously read analog pins. So by setting the correct set on, you can get readings from each photodiode.

This is just a rough idea, the transistor may mess with the readings, but im sure there must be a way to rectify this. Can someone tell me if/how this can be done correctly?