Electronics-Basics

Video Do electrons flow from positive to negative? Or do they flow from negative to positive? This AddOhms tutorial looks at the difference between Conventional Flow and Electron Flow. James also addresses whether or not his drawings are incorrect. Current Flow Direction Show Notes Ben Franklin by Duplessis 20 [via wikicommons]

Video Switching regulators make use of the energy storage properties of capacitors and inductors. A transistor, or switch, controls the charging and discharging. This method makes for an efficient regulator but can be difficult to design. Show Notes Here are links to the products mentioned in AddOhms #18:

The LM7805 is a very popular voltage regulator. Curious about how it works? In this AddOhms Tutorial, we look at what is a Linear Voltage Regulator and how to use them in your circuits. Linear Voltage Regulators Show Notes Related Datasheets LM7805 [Fairchild] NCP1117 [On Semiconductor] PIR Sensor [Adafruit] Interesting Links Written Tutorial on Regulators [ Baldengineer.com] TO-220 Information [Wikipedia] TO-220 Heatsink [Adafruit] Choosing the right LDO [All About Circuits]

There is nothing more frustrating than a push button that seems to work at random. The good news is the fix is pretty simple: a resistor. It may not seem obvious when you first start working with electronics but a “floating pin” doesn’t have a defined “high” or “low” level. Remember from the Analog and Digital video, that Digital Electronics has defined voltage levels. Well, when you don’t connect anything to the I/O pin of your microcontroller, the voltage level is undefined!

https://youtu.be/EQtwsWJuUPs Understanding voltage dividers means understanding Ohm’s Law. A common use for a voltage divider in most projects is to monitor a battery. Say you are powering your circuit with a 9V or 12V battery. Microcontroller boards don’t do well with those voltages. In a future video, we’ll come back and look at more circuits that can use voltage dividers. Episode Notes Correction: There is a mistake around 3:00. I say “91 millivolts” and I should have said “910 millivolts!”