How to Create the Schematic Symbol of LT1302-5 Step Up DC/DC Converter in SoloCapture

In this tutorial, we will show you how to create a custom schematic symbol (LT1302-5 Step Up DC/DC Converter is chosen for this tutorial) in SoloCapture. Creating a new library, drawing the part outline, adding pins, assigning the pin and part properties are explained in detail.

What is a DC-DC Step Up/Step Down Converter?

First of all we have to find what is a DC-DC Converter? Basically a DC-DC Converter is an electronic circuitry comprising of electronics components. These components includes some passive components like resistors, capacitors and inductors and some switching components like BJT’s (Bi-polar Junction Transistor’s) or thyristors. The purpose of the DC-DC converter is to convert fixed DC-DC voltages into fixed or variable DC voltages.

DC-DC Converters comes under the field of Power Electronics. In a lot of industrial and power applications, we required to convert a DC voltage into some other levels of DC voltages or in variable voltages. For these purposes we use a DC-DC Converter Circuitry.

DC Converter can be imagined as a DC equivalent of an AC transformer having a continuously variable turn’s ratio. DC-DC converter can be used to step up and step down a DC voltage source as like a transformer.

### Uses of DC-DC Converters

•   DC-DC converters are commonly used for motor control buildings lifts, automobiles, ships, trolley cars, forklift trucks.

•   These provide very fast dynamics, best efficiency and smooth acceleration.

•   These can also be used in regeneration of energy from braking of DC motors by returning back the energy into power supply. The regeneration of this energy results in savings for transportation systems with frequent stops.

•   DC-DC converters are also used in conjunction with an inductor, so that to generate a DC current source that can be used for the current source inverter.

•   Most importantly, DC-DC converters are used in DC voltage regulators, to regulate the DC output.

•   These play an important role in the portable devices, like digital cameras, laptops, Mobile phones, which requires power from batteries initially. These types of devices have a number of circuit distributions, each of which requires a different voltage value source to operate. Instead of placing a number of batteries in these devices to complete the need of the required voltages, we used DC to DC converters.

Temperature Sensors – Types and Applications

In this article, we will discuss the various types of temperature sensors and how to use a temperature sensor for a particular application.

Temperature is a physical parameter that is measured in units of degrees. It is a critical part of any process to measure accurate temperature. The typical applications requiring accurate temperature measurements include medical applications, biology research, electrical or electronic studies, materials research, and thermal characterization of electrical product.

A device used to measure amount of heat energy that allow us to detect a physical change in temperature, producing either a digital or analog output is known as a Temperature Sensor.

## Basic Physical Types of Temperature Sensors

In general, there are two sensing methods:

1. Contact

Contact temperature sensors are in physical contact with the object or substance. They can be used to measure temperature of solids, liquids or gases.

2. Non-contact

Non-contact temperature sensors detect temperature by intercepting a portion of emitted infrared energy of the object or substance, and sensing its intensity. They can be used to measure temperature of only solids and liquids. It is not possible to use them on gases because of their transparent nature.

## Types of Temperature Sensors

There are many different types of temperature sensors available that vary from simple on/off thermostatic devices which control a domestic hot water system to highly sensitive semiconductor types which can control complex process control plants. The two basic types of contact and non-contact temperature sensors are further classified into resistive, voltage, and electromechanical sensors. The three most commonly used temperature sensors include

• Thermistors,
• Resistance temperature detectors (RTDs), and
• Thermocouples

These temperature sensors differ from each other in terms of operating parameters. For moderate temperature range applications, solid state sensors are also available which provide the advantage of easy interface and built-in signal conditioning.

Thermistor

Thermistor is a temperature sensitive resistor that changes its physical resistance with the change in temperature. Generally, thermistors are made from ceramic material semiconductor, such as cobalt, manganese or nickel oxides coated in glass. It is formed into small pressed hermetically sealed discs that give relatively fast response to any temperature changes.

NTC Type Thermistor (Epcos)

Electronic Components Part 1: Resistors

Having known the electronics classification (Understanding Electronics – Analogue, Digital and Mixed Type Signals) it’s time to proceed further. In this article we will try to identify various electronics components within a PCB (Printed Circuit Board), know how those are classified and how can we use them to make our own electronics projects? If you have ever opened any electronics device you would have seen something like below pictures.

Figure 1 – Printed Circuit Board (mainboard of a computer)

These kind of attractive pieces of boards are called Printed Circuit Board. Now recall article 1 learning where we learned how electric current flows from one end to other via some specific path called circuit. Thus we need to build that specific path to harness the flow of electrons (current). There can be many ways to make this happen. Of course we need a good electric conductor first. If you don’t know what are conductors, semiconductors or insulators, please Google those for your basic understanding. So we require some kind of a conductor to carry electrons. A copper wire can do this task, any piece of metal can do this but would it then be appropriate to use any random metal pieces or wires inside any of our designed machines? Just imagine how it will look if we use any random pieces of metals or wires hanging inside our CPU instead of a motherboard! To resolve this smart people came out with an amazing invention called Printed Circuit Board. Printed Circuit Board or PCB is nothing but well planned shape of an insulator on which different traces of copper are printed for the current to flow.

Figure 2 (left) below shows an unpopulated PCB i.e. it is not populated with electronics products. Whereas the same PCB in Figure 2 (right) is populated with suitable components. In some other tutorial we will learn about various terminologies used in PCB.

Understanding Electronics – Analog, Digital and Mixed Type Signals

In the first article we tried to understand what is the driving force behind all modern gadgets? i.e. What is Electronics? How it differs from Electrical engineering? Three basic terms, Voltage, Current and Resistor and how these three are related using Ohm’s Law. Now in this article we will try to learn how Electronics is categorized into Analogue, Digital and Mixed Signals.

But before moving further let’s understand few limitations of Ohm’s Law. Sometimes I wonder how can it be termed as a Law when it is limited? Though let’s call it the same as others do. As stated in Part 1, Ohm’s Law says that “current through a conductor between two points is directly proportional to the potential difference across the two points.”

$V\propto I$

where V is the voltage and I is the current.

Unfortunately this is not always true. If it would have been that true, we wouldn’t have to bother about learning complex analysis of current and voltage. Electronics would have been much simpler.

The limitations of Ohm’s Law are:

1. Ohm’s Law is limited only to linear devices. It does not apply to non-linear devices such as Zener diodes, Voltage Regulator tubes. (This is just for your information and if you have not understood this, worry not since this won’t be that useful for our practical tutorials.)
2. Ohm’s Law holds true for metal conductors at constant temperature. If there are frequent changes in temperature Ohm’s Law will fail.
3. Ohm’s Law holds true only below certain frequencies. If you are working with very high frequency clock pulses (in GHz), pity Ohm’s Law fails. Resistor will then become an inductor in parallel to capacitor. (This holds some importance at advance level of designing, but as of now you are allowed to forget this.)

Coming back to our topics, how are Electronics circuits classified?

All Electronics can be broadly classified into two major branches: Analogue (Analog) and Digital.

Essential Tools for Electronic Experimenting

As, we all know that Electronic experimenting is an important part for electronic projects. We have previously discussed how mostly projects involve hardware for working purposes. And this is the reason one need to know about all the essential tools for experimentation in the lab.

People usually do not consider listing down all the essential tools before starting a project. But it can cost you with real trouble and create problems even in the middle of project putting extra load on budget and time wastage. So you should know about all the tools before starting a project as a high priority preference.