Basic Electricity and Electronic Devices Essay Example

to the wires. Similarly, thick layers of plastic are utilized for safety purposes in insulating high voltage power lines. However, if the insulation breaks and exposes the wire, it becomes dangerous and poses a risk.

Resistance is measured in ohms, named after Ohm Ohms who worked with electricity as a young boy in Germany. The range of resistor values commonly falls between 100 ohms to 100,000 ohms. Each resistor is labeled with colored stripes indicating its specific resistance value. More information on resistors and how to calculate their values can be found in the Resistor Values section.

Variable resistors are another common component that allows for adjustment of their resistance through a dial or knob mechanism. By modifying the resistance level, current can be controlled accordingly. Increasing resistance leads to decreased current flow and lower volume levels while decreasing resistance results in increased current flow and higher volume levels. The overall value of a variable resistor is determined by its highest resistance value.A potentiometer, also known as a variable resistor with a 500 ohm rating, can be adjusted to have a resistance ranging from 0 ohms to 500 ohms. This versatile component is capable of creating either a short circuit or an open circuit depending on its position. For instance, in the case of a light switch, when it is turned ON, it creates a short circuit that allows current to flow and lights up the room. Conversely, when the switch is turned OFF, an open circuit is formed which interrupts the current flow and turns off the lights. Teachers can utilize this effect to maintain control over noisy classrooms by simulating connectivity with the switch ON

and no connection established when it is OFF.

To effectively construct our projects, we will employ a breadboard containing metal strips beneath its surface made from copper. These metal strips serve as connections between various holes present on top of the board, allowing easy assembly of circuits by linking components together. Components are securely inserted into these holes due to design features that hold them in place. Each hole corresponds to a specific metal strip running underneath it, creating nodes within the circuit where two components are connected together.The breadboard used in this circuit has interconnected holes and metal strips underneath them to establish connections between components. Power supply connections are typically made using rows of connected holes called nodes. The row with a blue strip is for negative voltage or ground, while the row with a red strip is for positive voltage. Components are placed on the breadboard and connected using jumper wires to create a circuit. Once there is a path from the positive supply node to the negative supply node through wires and components, power can be activated and current flows through the circuit. When resistors are used, they can be connected in series or parallel on the breadboard. For chips with multiple legs (CICS), they should be positioned across the dividing line so that half of their legs are on each side of the board. A completed circuit may resemble what is shown below, where two small breadboards were used. Transistors and LEDs were introduced as essential components in Section 1.2 of this setup.The above featured LED is capable of emitting light as it functions as a light-emitting diode device. LEDs are

available in various colors such as red, yellow, green, and blue. The term LED stands for Light Emitting Diode. If you are not familiar with diodes, please refer to Basic Components in section 1.2.

It is important to note that diodes, including LEDs, only allow current flow in one direction. To make an LED work properly, a voltage supply and resistor are necessary components. Without a resistor, the low resistance of the LED may cause it to burn out. Similarly, without a power supply, the LED will not function correctly.

To set up the circuit and make the LED light up:
1. Identify the longer leg of the LED as its positive leg.
2. Place the LED on a breadboard with its positive leg in one row and negative leg in another row.
3. Connect one leg of a 2.K ohm resistor (either one) in the same row as the LED's negative leg and place the other leg in an empty row.
4. Disconnect the power supply adapter from its source and insert its ground end (black wire) into a sideways row with a blue stripe.Insert its positive end (red wire) into a sideways row with a red stripe.
5.To connect the positive power row to the positive leg of the LED, use a short red Jumper wire.Also connect
the ground row to
the resistor using
a short black Jumper wire.The components' layout on
the breadboard is shown
in
the provided picture.After plugging in
and connecting your power supply adapter,
the
LED should light upThe text explains that in a circuit, current flows from the positive leg through the LED to the negative leg. If the LED is reversed, it will not light

up because there is no current flow from the negative to positive leg. Some people think that placing the resistor before the LED restricts current, but regardless of its position, a resistor will emit a current. Ohm's Law (I = VT/R) can be used to calculate current by considering voltage across the resistor (VT) and resistance (R). In this specific circuit example, Ohm's Law can be applied to calculate current by taking into account a 1.4-volt voltage drop across the LED when it is on. With a 12-volt source connected to its positive leg, its negative leg will have 10.6 volts. The voltage across the resistor allows us to determine current using Ohm's Law: (10.6 - O) / 2200 = 0.048 Amperes or 4.8 mA for both LED and resistor in this setup mentioned earlier. To adjust LED brightness without affecting other components, resistors can be modified accordingly or transistors can be used for independent control over LEDs as explained previously.Transistors are important switches in modern electronics and widely recognized electrical componentsMillions of transistors are utilized in constructing Pentium processors, showcasing their significance in today's technology. Transistors typically have three legs: Collector (C), Base (B), and Emitter (E). These labels may be found on one side of the transistor, which has a round side and a flat side. The Collector leg is on the left, the Base leg is in the middle, and the Emitter leg is on the right. This symbol represents a transistor in circuit drawings.

The Base acts as an On/Off switch for the transistor. When current flows to the Base, it allows current flow from the Collector to the Emitter ("The Switch

is On"). If no current flows to the Base, there is no path from Collector to Emitter ("The Switch is Off").

To incorporate a transistor into an LED circuit setup, create a basic circuit with both components. Before inserting a transistor into a breadboard, unplug power supply from its adapter.Separate and place each leg of the transistor onto different rows inthe breadboard.Place Collector leg in same row as ground-connected resistor's leg.Move jumper wire from ground to 2.K ohm resistor to Emitter of transistor.Position one leg of kick ohm resistor in line with both Base of transistor and empty row.Your breadboard should look like provided picture.Insert one end of a yellow Jumper wire into positive row (next to red line) and connect its other end to row where you find kick ohm resistor's unconnected end from BaseAfter reconnecting the power supply, both the LED and transistor will turn on, causing the LED to illuminate. Next, move one end of the yellow Jumper wire from the positive row to the ground row next to a blue line. Disconnecting the yellow Jumper wire from the positive power supply will stop current flow through Base, resulting in turning off the transistor and preventing current flow through LED. It is important to note that there is minimal current flowing through kick resistor, which plays a significant role in controlling larger currents using Ohm's Law elsewhere in the circuit. To determine currents along Input-Base path and through LED, we will utilize Ohm's Law while considering two important facts about transistors: when a transistor is on, voltage at Base exceeds Emitter by 0.6 volts.When a transistor is turned on, the Collector has a

voltage that is 0.2 volts higher than the Emitter. In the circuit where the kick resistor is connected to VIVID, the current flowing through the kick resistor can be calculated by dividing (12 - 0.6) by 100000, resulting in 0.000114 A or 0.114 mA. Similarly, the current flowing through the 2.K ohm resistor can be found by dividing (10.6 - 0.2) by 2200, giving us 0.0047 A or 4.7 mA.

If we want more current to pass through the LED, we can use a smaller resistor instead of using a resistor with a resistance value of 2200 ohms. However, this will also change the amount of current flowing through the Input line.

Using low power circuits allows us to control power-intensive devices like electric motors at an affordable cost.

Ultimately, you will learn how to utilize a microelectronic component that functions as a basic computer. While it may not directly provide enough current for lights and motors, it can activate transistors capable of handling significant currents for such devices.

It's important to note that when considering Ohm's law, no current flows through a transistor when it is off.

In digital devices, there are two values known as '1' and '0'. A '1' represents a voltage typically at 5 volts while '0' indicates a voltage at zero volts.
An inverter, also known as a NOT gate, is an important digital device found in modern electronics. It produces the opposite output of its input, with '0' input resulting in '1' output and vice versa. To demonstrate transistor practice, we will use a previously built inverter circuit as the first inverter. We will create a circuit using two inverters to observe their functionality. The

second inverter will be connected to the first one according to the provided circuit diagram.

To build this circuit, we need to take the transistor circuit from the first inverter and connect its input resistor to a yellow jumper wire. A second identical circuit for the second inverter should be built without including the yellow jumper wire connected to the resistor.

To connect the output of the first inverter to the input of the second inverter, place one end of a jumper wire on rows with holes containing a 2.K ohm resistor and transistor Collector (output of first inverter). Place another end on rows with holes containing a resistor leg for connecting it tothe second inverter's input.

To confirm correct construction, activate the first inverter and ensure that LED remains deactivated for the second inverter. Finally, connect OVA (the ground row) to the input of both inverters before turning off its switch.When the LED is turned off, the first inverter should go off while the second inverter should come on. If this does not happen, check for any metal parts touching and ensure accurate connections of all components. The input can be connected to either IV or OVA. When connected to IV, it activates the transistor in the first inverter and lights up its LED, setting Inverter Output voltage at 0.V. The output of this first Inverter is then linked to the input of a second one. At this point, there is a small voltage of 0.IV at this input which keeps its transistor switched off. When connecting Inverter Input to OVA, it turns off its transistor resulting in a very dim LED glow; however, there still exists

a small current flowing through this LED towards reaching subsequent inverters. As a result, the voltage at Inverter Output increases compelling activation of transistors within these succeeding inverters. Consequently, the LEDs associated with these latter inverters also illuminate.
To determine voltage levels at output from initial inveter (10.IV), Ohm's law proves useful.The transistor in the first inverter does not have any current flowing through it.Instead, the current path goes through the first LED, a 2.K resistor,a kick resistor,and finally through thseconfd transistor to ground.The negative side ofthe firsatLED maintainsa fixed voltaggeof10.IV due ttotheLEDitself.Similarly,the baseofthe secondttransistorkeepsafixedvoltageof 0.IV thanks tothetransistorApplying Ohm's law and considering the two voltages, it can be determined that the middle point has a voltage of 10.IV. To find the voltage at the point between the 2.K resistor and kick resistor, one must calculate the current and use Form 1 of Ohm's law. When switching from Veto IV as input, it is observed that activating the first stage deactivates the second stage, demonstrating an inverting action of Inverters. In complex electronic designs, building circuits from scratch becomes challenging; hence, pre-built circuits like Integrated Circuits (ICCs) are used instead. These ICCs contain multiple connected transistors enclosed within plastic or ceramic material with metal pins for connections with other devices. Various types of ICCs can be purchased, ranging from simple ones similar to LED and Transistor circuits to more complex ones like a Pentium Processor.

The 555 integrated circuit (C) is designed to switch between O volts and PVC when there is a change in input, remaining at PVC for a specific duration before returning to O volts. This voltage switching creates pulses. An oscillator generates an endless

series of pulses where the output consistently alternates between O volts and PVC. Most digital circuits incorporate an oscillator referred to as a clock which measures time by counting these pulses.

In this section, we will explore how the 555 timer can generate this clock signal. If you are already familiar with capacitors, you can skip this section.The left image above displays two capacitors, one with a longer positive leg and the other with a shorter negative leg. The right image illustrates capacitors in circuit drawings. It is crucial to correctly position the positive and negative legs when inserting them into a circuit. However, some capacitors in this kit do not have this distinction and can be inserted in either direction.

Capacitors function similarly to rechargeable batteries but store only a fraction of the energy. Nevertheless, larger capacitors like those found in old TVs can hold a significant amount of charge and may still produce sparks even after being disconnected from a power source for an extended period.

Like rechargeable batteries, capacitors require time to charge. If a 12-volt supply charges a capacitor, its voltage will gradually rise from zero volts to 12 volts. The graph below provides an illustration of the voltage change during the charging process.

The same principle applies during discharging; if a fully charged capacitor at 12 volts connects both legs to ground, it will discharge over time until reaching zero volts. The provided graph depicts the voltage changes throughout the discharging process.

To control the speed at which a capacitor charges and discharges, resistors are utilized.Capacitors have different values based on their ability to store electricity. Larger capacitors can store more energy, but they take

longer to charge and discharge. In this kit, there are 2 fop capacitors (33 picadors or 0.000000000033 Farads), 2 pouf capacitors (measured in Farad instead of isobaric or microfarad value), and 2 buff capacitors with a maximum voltage rating of 25 volts. It's important not to exceed this voltage as it can damage the buff capacitors. However, our power supply only provides 12 volts.

The 555 timer is made up of simple transistors that act as on/off switches without any time sense. When voltage is applied, they turn on; when it's removed, they turn off. Therefore, they cannot generate a pulse by themselves. To create a pulse, other components in the circuit diagram below are used, including a capacitor and resistor.

In this circuit design, we have the choice to activate a switch and start charging the capacitor. The resistor determines how quickly the capacitor charges; higher resistance leads to longer charging times. The stored voltage in the capacitor can then be used as an input for another switch.

Initially, when the voltage is at zero, nothing happens with this second switch. However, as the capacitor charges up to a certain level, it triggers activation of the second switch.The 555 timer operates by connecting its Output pin to PVC through flipping the first switch, which starts charging the capacitor. When the voltage across the capacitor reaches 2/3 PVC or PVC multiplied by 2/3, it activates the second switch and reduces the output voltage to zero volts. The following is a display of pinout information for thå 555 timer, providing detailed explanations about each pin. Pin 2 functions as an ON switch for generating pulses and is labeled "Trigger."

The line above "Trigger" indicates that voltage levels are opposite from what would usually be expected. To activate this switch, O volts must be applied to pin 2. This behavior is known as "Active Low," commonly observed in ICC inputs due to transistor circuits' inverted nature demonstrated in LED and Transistor Tutorial. Pin 6 acts as an OFF switch for generating pulses where we connect the positive side of the capacitor to a specific pin and ground the negative side. When Pin 2 (Trigger) has a voltage level of PVC, the 555 keeps Pin 7 at O volts. Once Pin 2 becomes O volts, Pin 7 is no longer held at O volts leading to an increase in its voltage as the capacitor charges through a resistor connected to PVC.Pin 3 serves as the output for generated pulse with initially having a voltage of O voltsApplying 0 volts to Pin 2 of the 555 chip triggers it, causing Pin 3 to generate a PVC signal. This signal is maintained until Pin 6 reaches two-thirds of the voltage at Pin 7. At this point, the voltage at Pin 3 is pulled down to ground by the chip, creating a pulse. The capacitor discharges and brings down the voltage at Pin 7 as well. To visualize these pulses, an LED can be connected to output Pin 3. When the voltage is 0 volts, the LED remains off; when it's PVC, it turns on. To assemble this circuit correctly on a breadboard with proper power connections, refer to the provided diagram where pin numbering starts from a half circle or dot/hole indicating pin number one. Before powering up,

ensure that Jumper wires are connected between the red and blue power rows on both sides of the board for easy access to both PVC and Ground lines from either side of the board. If wires are too short, join them together in a row of holes for positive power (PVC), while joining them in a different row is necessary for ground connection. ConnectPin1togroundandPin8aswellasPin4toPVC.FortheLEDcomponent,connectitspositivelegt oa330ohm resistor and its negative legtoground.Then linktheotherlegoftheresistorwiththeoutputatPin3.AdditionallyconnectingPin7withPVCrequiresanaskresistor(RA=ASK).Furthermore,it isnecessaryto connectPin7toPin6usingaJumperwire