Electronics Cookbook

Chapter 21. Tools

21.0 Introduction

This chapter explains how to use some of the most common electronic tools and test equipment. This includes both instruments for measurement such as multimeters and oscilloscopes and also simulation software that can be useful during design, especially when dealing with analog electronics.

21.1 Use a Lab Power Supply

Problem

You want to know how to correctly use a lab power supply.

Solution

To correctly use a lab power supply, follow these steps:

1. Set the voltage to the voltage your circuit needs.
2. Set the current limiting to slightly higher than the expected current consumption of your circuit.
3. Turn on the output and watch the voltage display. If too much current is being drawn, the voltage will drop, indicating that something is wrong.

Discussion

Aside from a multimeter, the lab power supply is probably the most useful piece of test equipment you can own. Owning one will save you vast amounts of time in the long run because you won’t have to hunt around for batteries and cobble together power supplies and reduce the chance of accidental destruction of components when prototyping.

Figure 21-1 shows a typical lab power supply capable of supplying up to 22V at 5A.

Figure 21-1. A Lab Power Supply

The top line of the display shows the voltage and the bottom, the current. When the output is off, the voltage knob allows you to set the voltage. ...