The paper "Car Indicator Design" is a great example of a report on design and technology. In this particular project, the design, simulation, as well as building of a circuit that functions as a car direction indicator, involved comprehensive research and selection of a preferred idea before obtaining a detailed design. The circuit system of the car indicator was expected to employ the use of electronic signals and controls. When the car is about to change direction either to the left or to the right a switch is activated.
The activated switch measures the signals and currents in the circuit system, and then the headlights are electronically activated. A computerized electronic circuit system on the dashboard switches on or blinks the indicator lights (Grout, 2008). The indicator circuit system designed in this project was also expected to possess the sensing capabilities to be able to sense the current that flows through the circuit with a very small magnitude. The small magnitude of the current is a representation of the resistance fraction, which results in the current referred to as the current sensing resistor.
When the flow of current takes place, the development of a fraction of voltage is experienced across the resistor. However, this particular currency is not sufficient to lead to the production of an appreciable drop in voltage across the devices in series with it. An op amplifier is used in the amplification of the small voltage into a signal that activates other indicator devices (Candela, 2009). Objective This project was expected to meet the specified objectives as follows: Designing and building of a circuit system to function as a car direction indicator using 555 timer Incorporation yellow lights that blink while indicating the driver’ s intention of turning right or left Final design Several design ideas were considered before a final design was arrived at.
The final circuit obtained in this project was broken down into smaller subsystems, which were separately described using block diagrams as indicated below. Bi-stable The bi-stable mode is also referred to as the Schmitt trigger mode. This kind of timer functions as a simple flip-flop. In this particular case, the reset inputs, as well as the trigger, are held at a higher position through the pull-up resistor while the pin at the threshold input is left in a floating position.
The configuration is such that when the trigger is shortly pulled towards the ground, the output pin is transitioned to a high state. When the pulling of the reset pin takes place towards the ground, it plays the role of resets, which is responsible for the transitioning of the output to a low state. In the case of a bi-stable configuration, there are no timing capacitors needed. The pin that controls voltage is linked to the ground through a capacitor with a small value that is between 0.01 uF and 0.1 uF.
Pin 7, which is responsible for the discharge, remains in a floating position (Grout, 2008). Block diagram of a bi-stable mode A stable In this particular model, the timer presents a continuous and steady stream of pulses that are rectangular in nature and with a specific frequency. A resistor is linked in the middle of the discharge pin and the voltage VCC. Another resistor is in a position between the trigger and the discharge pin as well as the threshold pins having a common node.
Therefore, the capacitor obtains charge through the resistors R1 and R2. The capacitor is then discharged through the resistor R2. The impedance within pin 7 is low towards the ground and therefore it is discharged via the capacitor. In this, a stable mode, the frequency of the pulse stream is dependent on the magnitudes of R1, R2 as well as C (Candela, 2009).