As no modern power supply is complete without one of these, its important we have a good understanding of what these components are all about.
Youtube video, suitable whether of not you have the board with you.
See board images.
Tutorial guide for when you have the board with you.
Voltage Regulators are an extremely useful component and are used in the power supply of most circuits not powered by batteries. Let’s have a look at how they work and what they do.
Ensure all the toggle switches are down in the off position and then move the rotary switch to position C. The green display shows the supply voltage to the two regulators on the board.
We will look at the one on the left first – this is a fixed voltage regulator. They come in a number of different voltage options - one is rated at 5 volts. You can see the output voltage in the display, it's just under that target of 5 volts.
Turn on the two LED lights connected to this regulator using the first two switches to add a load to this circuit. You will see the supply voltage drop a little but the output voltage of the regulator will not change. If you move the rotary switch to position B the supply voltage will be reduced but the regulated voltage still stays the same.
The output voltage from the second regulated can be changed by the potentiometer (variable resistor) controlled by the yellow knob. But again, the voltage will not change if you use the switches here increase the current by turning the LEDs on. You will see the LEDs dim as the voltage gets very low with the rotary switch at position A.
The input voltage to a regulator is always more than the output. If you move the rotary switch to position A and turn the first two small switches on, you will see the fixed regulators output voltage drop, this is because the input voltage is not high enough. You really need input to be a couple of volts greater than the required output.
Note that both regulators are in heat sinks, this is because they can get hot if the input voltage is much greater than the output and the current is high as the regulator tuns the additional energy into heat. The regulators on this board will work up to 1.5 amps.