Assignment 1 Course Outcome 3

Assignment 1
Course Outcome 3: Ability to propose an analogue electronic circuit given any electronic components and specification.

Programme Outcomes 4: Conduct investigation of complex engineering problems using research-based knowledge and research methods including design of experiments, analysis and interpretation of data, and synthesis of information to provide valid conclusion
Course Outcome 3: Ability to propose an analogue electronic circuit given any electronic components and specification.

Programme Outcomes 4: Conduct investigation of complex engineering problems using research-based knowledge and research methods including design of experiments, analysis and interpretation of data, and synthesis of information to provide valid conclusion

Question
Figure 1 shows a shoe cabinet. For safety reasons, it is advisable if we could see the inside of the cabinet. Propose a circuit design that could help you see more of the inside of the cabinet using 555 timer. The 555 timer IC will trigger the LED for some time and then automatically turn it off. You may also use other electronics components in your design. Draw your block diagram and circuit diagram.
Please include your references such as book references, journal/conference articles, datasheets, calculations, and websites.

BIOMEDICAL ELECTRONIC ENGINEERNG PROGRAM
SCHOOL OF MECHATRONIC ENGINEERING
UNIVERSITY MALYSIA PERLIS (UNIMAP)
ASSIGNMENT 1
ENT 216 ANALOGUE ELECTRONICS 2
NAME:SYAFIQAH ZAWANAH ZAHRAA’ BINTI MOHAMED ZAHARI
MATRIC NO:171151519
DATE OF SUBMISSION:3 DECEMBER 2018
OBJECTIVE
To analyze IC 555 Timer and design a system that will be automatically turn off or turn on the light by presence and absence of the light.

INTRODUCTION
WHAT IS IC 555 TIMER?
IC 556 Timer is a integrated circuit consists of :
2 comparators
1 Flip-Flop
1 discharge transistor
1 Resistive voltage divider
BLOCK DIAGRAM
IC 555 Timer comes in 8 Pin as the figures below:

PIN 1: Ground Terminal
All the voltages in the circuit are measured respect to the ground.

PIN 2 : Trigger Terminal
It is an inverting input of a comparator and also is responsible to the transition of flip –flop in the IC from set to reset. It also used to feed the trigger input as the IC 555 Timer is set up as monostable multivibrator. The output of this IC 555 Timer is depending on the amplitude of the external trigger pulse that is applied to this pin. DC level greater than Vcc/3 with a negative pulse will be applied to this terminal. As the trigger passes through Vcc/3 in the negative edge , the lower comparator output will become high and the complementaryof Q becomes zero. Therefore, the IC 555 Timer will have high output voltage in quasi stable state.

PIN 3: Output Terminal
This pin control the output of this Timer. Load can be connected in two ways to the output terminal. First is by connected it between output pin ( pin 3) and ground pin ( pin 1) . Second , by connect it between pin 3 and supply pin ( pin 8). Connection between output and ground supply pin is known as normally on load whereas the connection between output and ground pin is known as normally off load.

PIN 4: Reset Terminal
When a negative pulse is applied to pin 4 this IC Timer will be reset and disabled. If this pin is not going to be used as a rest purpose it will be connected to + Vcc to avoid any possibility of false triggering.

PIN 5: Control Voltage
This pin will controlled the threshold and trigger levels of this timer. To modulate the output waveform ,the external voltage will be applied to this pin.Therefore, when the comparator is switched, the amount of voltage applied to this terminal can be decide. If this pin is not used , it should be bypassed to ground through 0.01 micro Farad in order to avoid any noise problem.

PIN 6: Threshold Terminal
PIN 7 :Discharge Terminal
PIN 8 : Supply Terminal
DISHARGE AND DISCHARGE
REFERENCE

Electronics Components: How the 555 Timer Chip Works


http://www.circuitstoday.com/555-timer