This blog post on series vs. parallel circuits is an excerpt from Level A of our Intro to Robotics program. Level A covers building circuits, using a Raspberry Pi, and writing common code commands in Python. It contains 18 lessons including 70+ videos and 45 projects and activities. Sample lessons and a full scope and sequence for Level A can be found here.
When you are first getting started working with basic electronic components, you will generally build very simple circuits. A single path running from the anode (+) of the battery, through a resistor, through an LED, and then back to the cathode (-) of the battery. This is known as a series: one path of components running off the source battery.
But most projects or real-life applications would run in what’s known as a parallel circuit. When running in parallel the current runs from the positive terminal of the battery, splits along multiple paths to power components, and then runs back to the negative terminal of the battery.
While series circuits are simpler, they also have some significant limitations. Mainly that you would need a higher voltage battery to run anything more than a few simple components. Instead, circuits are normally run in parallel which allows the battery voltage to feed equally to all paths within the circuit. So, looking at the first picture above, with a 3-volt battery, 3-volts will feed resistor 1 and LED 1. In second picture above, a 3-volt battery will provide 3-volts of power to resistor 1 and LED 1 and 3-volts to resistor 2 and LED 2. Therefore, running circuits in parallel essentially makes the full battery voltage available across multiple paths.
Rather than being limited to a handful of components, parallel circuits allow for much more complex circuits like the one below where the full voltage of the battery is running through each of the 11 branches each containing a resistor and blue LED:
This blog post on series vs. parallel circuits is an excerpt from Level A of our Intro to Robotics program. Level A covers building circuits, using a Raspberry Pi, and writing common code commands in Python. It contains 18 lessons including 70+ videos and 45 projects and activities. Sample lessons and a full scope and sequence for Level A can be found here.