The first part of my question relates to a circuit I am builing following Nick Gammon's diagram for using a Max7219 chip with a common cathode 4 digit 7 segment display. In the cicuit there is this bit which has capacitors in parallel:
I realize that the capacitor to the right is an electrolytic capacitor, but the capacitor to the left is perplexing me! Would that be a ceramic disc capacitor? Also, when I am looking to buy these 0.1?F capacitors, if I look for ceramic capacitors there are ones that look sort of terracotta-coloured and called "ceramic disc" and there are others which are blue, and these are usually labelled as "ceramic". Is there any difference between these apart from colour? I've googled but perhaps I am not using the right search terms!
The second part of my question is again about another circuit diagram that I would like to follow and involves capacitors again. I have been testing an optical sensor for measuring RPM, but now I am going to test a couple of different Hall Sensors. The Hall Sensor I am most taken with is the TLE4905L (datasheet here). At the end of the datasheet, they have a potentially helpful circuit diagram, which looks like this:
The questions I am hoping people can help me with are: 1) Are the parts in the circuit for a 5V setup like with the arduino? It's not clear to me...the bit about a "mainframe"(!!!) has me puzzled too :astonished: I take it that my arduino is the "mainframe"! :) 2) If I enable the arduino's internal pull-up resistor, does the 1.2k resistor in the circuit then become unnecessary? 3) Am I looking for ceramic disc capacitors again for the capacitors in this circuit? Also, is the value of those capacitors OK to put in a 5V circuit?
I hope it is OK to ask all of these questions in one thread!