Electronics Design :-

Group Asignment

use the test equipment in your lab to observe the operation of a microcontroller circuit board.

It would help us understand

1) The working of multimeter

2) Using Power Supply

3)Understand Test Equipment

4)Working of OScilloscope.

Multimeter:-

A multimeter is an electronic tool used to measure voltage, amps and resistance across circuits.By attaching two leads to different parts of an electrical system, professionals can use multimeters to detect levels of voltage and resistance, or changes in electrical currents. In the lab we used the multimeter to check the continuty in the circuit board and calculate the value of the resistence and measure the forward volatage.

In the lab used the oscillo scope.

oscillo

An oscilloscope is an instrument that graphically displays electrical signals and shows how those signals change over time. We can use oscilloscopes to measure electrical phenomena and quickly test, verify, and debug their circuit designs. The primary function of an oscilloscope is to measure voltage waves

Individual Assignment

This week Assignment redraw an echo hello-world board,add (at least) a button and LED (with current-limiting resistor) check the design rules, make it, and test it
extra credit: simulate its operation

Electronics Basics

comsym

1) Components Symbol

occ

2)What Is A Circuit?

Before you design an electronic project, you need to know what a circuit is and how to create one properly.
An electronic circuit is a circular path of conductors by which electric current can flow. A closed circuit is like a circle because it starts and ends at the same point forming a complete loop. Furthermore, a closed circuit allows electricity to flow from the (+) power to the (-) ground uninterrupted.if there is any break in the flow of electricity, this is known as an open circuit. As shown below, a switch in a circuit can cause it to be open or closed depending on it’s position.

3)Integrated Circuit (IC)

An integrated circuit is a circuit that’s been reduced in size to fit inside a tiny chip. This circuit contains electronic components like resistors and capacitors but on a much smaller scale. Integrated circuits come in different variations such as 555 timers, voltage regulators, microcontrollers and many more. Each pin on an IC is unique in terms of it’s function.

relay

4)Relay

A relay is an electrically operated switch that opens or closes when power is applied. Inside a relay is an electromagnet which controls a mechanical switch.

tran

5)Transistor

Transistor are tiny switches that turn a current on or off when triggered by an electric signal. In addition to being a switch, it can also be used to amplify electronic signals. A transistor is similar to a relay except with no moving parts.

led

6)Light-Emitting Diode (LED)

A light-emitting diode is like a standard diode in the fact that electrical current only flows in one direction. The main difference is an LED will emit light when electricity flows through it. Inside an LED there is an anode and cathode. Current always flows from the anode (+) to the cathode (-) and never in the opposite direction. The longer leg of the LED is the positive (anode) side.

diode

7)Diode

A diode allows electricity to flow in one direction and blocks it from flowing the opposite way. The diode’s primary role is to route electricity from taking an unwanted path within the circuit.

capa

8)Capacitor

Capacitors store electricity and then discharges it back into the circuit when there is a drop in voltage. A capacitor is like a rechargeable battery and can be charged and then discharged. The value is measured in F (Farad), nano Farad (nF) or pico Farad (pF) range.

ldr

9)Light-Dependent Resistor (LDR)

A light-dependent resistor is also a variable resistor but is controlled by the light versus turning a knob. The resistance in the circuit changes with the intensity of the light. These are often found in exterior lights that automatically turn on at dusk and off at dawn.

resistor

10)Resistor

Resistors are used to resist the flow of current or to control the voltage in a circuit. The amount of resistance that a resistor offers is measured in Ohms. Most resistors have colored stripes on the outside and this code will tell you it’s value of resistance. You can use a multimeter to determine the value of a resistor.

dmm

11)Digital Multimeter

A multimeter is a device that’s used to measure electric current (amps), voltage (volts) and resistance (ohms). It’s a great for troubleshooting circuits and is capable of measuring both AC and DC voltage.

kir

12)Kirchhoffs First Law – The Current Law, (KCL)

Kirchhoffs Current Law or KCL, states that the “total current or charge entering a junction or node is exactly equal to the charge leaving the node as it has no other place to go except to leave, as no charge is lost within the node“. In other words the algebraic sum of ALL the currents entering and leaving a node must be equal to zero, I(exiting) + I(entering) = 0. This idea by Kirchhoff is commonly known as the Conservation of Charge.

13)Microprocessor

Microprocessor Unit do not have memory . They use external memory to provide program and data storage. The program is typically stored in non-volatile memory, such as NAND or serial Flash. At start-up, this is loaded into an external DRAM and execution commences. This means the MPU will not be up and running as quickly as an MCU but the amount of DRAM and NVM you can connect to the processor is in the range of hundreds of Mbytes and even Gbytes for NAND.

14)Microcontroller

Micro Controller Unit uses on-chip embedded Flash memory in which to store and execute its program. Storing the program this way means the MCU having a shorter start-up period and executing code quickly. The only practical limitation to using embedded memory is that the total available memory space is finite. Most Flash MCU devices available on the market have a maximum of 2 Mbytes of Program memory. This may prove to be a limiting factor, depending on the application.

ATTiny 44,45 have 4 KB of Memory and ATTiny 85 have 8KB of memory

Schematic designing the Hello Echo World Board

For this I used the Eagle Software.

Create a new project

create a new schematic

Now Download the eagle fab library from here.Then i added the eagle fab library to the eagle/library directory and confirmed whetehr it is in use.

Then I added the components

Then i gave the value of the components

I made the connection using the 'Line' tool and 'Name' tool.

But in the assignment requires me to connect an LED and a push button, I updated the schematic diagram accommodating both.

The component can be moved, rotated and mirrored by clicking on the following icons from the tool bar, then click on the component itself.

Name the pins by typing name in the command line. Change the name to the desired(here VCC) in the popup.

name

My Final circuit was as following.

Check for errors using ERC button in the tool bar.

The output of my ERC check:

33p

The value of the current limiting resistor was calculated using V=IR

V-Forward voltage of LED (1.8 V)

I-Forward curent (20mA)

After i switched to Board Design

After this I checked the design rules.Initially the width under the clearnce tab was 6 mil but we changed it to 16 mil.

Note 1 Inch = 1000 Mils.For trace cut we use 1/64 Bit.so we calculated it to 15.625 mil and gave the width as 16 mils.

But on searching the fabacademy profiles of one of the student (Not remembering the name will update it later ) found the set of good designing rules.

similarly under sizes tab we gave 16 mils..

Then after this we used the auto rout features under the tools tab with high efforts

But I got errors the routs were intersecting and sometime it gives the routing for double sided PCB.I tried this with low efforts but same problem persisted

i asked my instructor regarding this problem Mr.Sheebu.He advised to do routing of the small circuit mannually.So finally i decided to redraw it again mannually. And suceeded.

10p