A Voltage regulator (aka Step down) is an electronic circuit that converts the input voltage to a lower output voltage.
For example. You’re running your droid with a 24V Setup. The 24V would destroy most of the electronics inside your droid. So you use a voltage regulator that converts the 24V to stable 5V so you can hook up your Arduinos etc.
This particular regulator it’s an LM2596
– Power In: 4,5-38V
– Power Out: 1.25-36,5V
– Output current: 2A (max 3A)
– Working temperature: -40 a + 85 ºC
– Operational frequency: 150KHz
– Efficiency: up to 92%
– Load regulation: +/-0,5%
– Voltage regulation: +/-2,5%
– Temperature protection: yes
– Size: 62mm x 38mm x 15mm