Proteus 1001: DC Motor Speed Control Circuit with 555

In the Proteus application, which we are getting more and more into, today we will make a new topic with you. In this article, we will not only do projects using the main simple circuit elements. In addition to these elements, today we will learn an important concept. This concept has provided us with so much convenience in today's electronics that it appears almost everywhere. The name of this concept we will learn is integrated. Then we will make a nice application together to reinforce it.

What is Integrated?

Integrateds (IC) are a small integrated circuit that contains a lot of circuit elements, ranging from resistors to semiconductor materials. They are usually made of silicon and are designed on a metal sheet. In general, the smallness of the integrateds, ease of use, is a serious part of today's electronics. When you even examine its internal structures alone, it is possible to find millions of transistors and similar circuit elements in a small area. This is one of the most important features that distinguishes it from the discrete circuit. The collection of so many elements into a small area gives another advantage. This advantage is speed. The fact that each element is located closely with each other in a small area causes the current to pass faster. This can be counted as another advantage for integrations. Integrated circuits are used in almost many technological instruments today. To give an example:

  • Computer
  • Phone
  • Camera

There are a lot of tools like that.

proteus 555 dc motor
proteus 555 dc motor

It has two types of integrated structures. One of them is THT and the other is SMD. It is possible to use THTs with tools such as breadboards and perforated plaques. Therefore, it provides us with a faster usage. SMD integrateds are produced so that they can be soldered directly on the circuit board. Otherwise, the leg numbers and similar characteristics of the integrated ones are the same. So how to number integrated legs?

proteus 555 dc motor
555 Integrated

As you can see, there are notches on the integrated ones. When enumeration each integration, we start by giving a number on the left side of this notch. Afterwards, this process continues as it is, counterclockwise. Actually, numbering is as simple as that.In addition, of course, each integrated has its own it characteristics. We recommend that you review the datasheets to find out.

What is DC Motor?

DC Motor is a type of electric motor that converts direct current energy into mechanical energy. DC motors are ubiquitous today. To give an example:

  • Automobile Industry
  • Fans
  • Industrial Equipment
  • Pumps

And they appear in many similar places. There are, of course, many varieties in itself. Therefore, it is best to choose a DC motor according to the area you will use. We've already told you about dc engine variants. These, respectively;

  1. Brushed DC Motors
  2. Brushless DC Motors
  3. Step Motors
  4. Servo Motors

They all have their own advantages and disadvantages.


As you can see from the title in today's application, we will make a DC Motor speed control circuit using the 555 integrated. Of course, this design can be of various kinds. We're going to show you one of them today. But first it is necessary to understand the internal structure of the 555 Integration. And going into the detail of the 555 integration in this article we recommend that you readthe first one, since it can make the writing very complicated, and we already have a detailed article on the 555 integration . In this way, you can understand the operation of the process more easily.

Required Materials

  • 555 Integrated
  • resistance
  • Diode 1N4001
  • Potentiometer
  • NPN and PNP transistor
  • DC Motor
  • Capacitor
proteus 555 dc motor
We're looking for the integrated in the same place.

Calling all elements, including integrated, is a really simple process. After we call all the staff, we move on to the process of setting up the circuit. In fact, its logic is not very complicated. You just need to know what you're using and why. Why is the capacitor there and at what intervals is the capacitor loaded? And until what interval we have to be able to answer questions such as how long this process takes place. In short, there are 2 OpAmps in our integration and they act as comparators in the circuit. One is the Trigger leg of the integration, and the other is the Threshold leg. The other two legs of the comparator go to the voltage dividers. The operating logic of the capacitor is as follows: First, they compare the values above the Voltage dividing resistors on the comparators. This value varies according to the value you will give in the feed. Since the capacitor is empty in the first place, it sends a value of 0 to the comparator in logistics. In this case, the comparator gives us a result accordingly, since there will be more voltage in the other leg of the comparator (values above voltage dividing resistors) depending on the trigger. This will be logistics 1. Of course, since the capacitor will work like this in both comparators in the first place, but if you pay attention this time, our logistics zero goes to the "plus" foot of the comparator to which the threshold leg is attached. Therefore, since there will be more voltage on the "minus" foot of the comparator, our result will be the opposite Of Logistics 0. These two results depend on the SR Latch part of the integration. It is better to interpret it here by looking at the SR Latch table. And as a result, SR sends one or zero commands to output after Latch. If it sends zero as output, the capacitor will not be able to transmit to the transistor we have seen, so the capacitor will be in a filling state. And this continues until the voltage value of the capacitor exceeds the voltage value in the "minus" leg of the comparator to which threshold is attached. As soon as it exceeds that voltage value, the capacitor filling stops because the transistor is turned on. He then proceeds to the discharge leg. This is how it goes in a cycle. The installation of the posiometer is already very simple. We can complete it by connecting the middle leg to the DC (7) foot.


proteus 555 dc motor With the posiometer you have seen, we can control the speed of the DC motor. In Proteus, you will be able to start and observe it in a much better way when you start and do a simulation of it. proteus 555 dc motor Now that we have completed our simulation, we have reached the end of this article. You can reinforce it nicely by doing it on your computer yourself.