Not gate
Download as DOCX, PDF0 likes2,141 views
This document describes designing a NOT gate circuit using an npn transistor. It explains the working of the NOT gate by complementing input signals of 0V and 5V to produce the opposite output voltage. The circuit uses an npn transistor, LED, resistors, battery, and toggle switches. Pushing the button simulates a high input, causing the transistor to saturate and current to bypass the LED, turning it off. Releasing the button simulates a low input, causing the transistor to cut off and current to flow through the LED, turning it on. The output was verified using a truth table to operate as a NOT gate.
Not gate
- 1. Aim To understand the working of NOT gate using npn transistor and to design a circuit of NOT gate using npn transistor, LED, push button type toggle switches and suitable resistances.
- 2. Introduction NOT gate is an Boolean operator based on the mathematical function of complement. It works on digital signal as its input which have only two states of voltages, low as 0V and high as 5V. NOT gate consists of electonic circuit of npn transistor having an input digital signal which can take r different combinations on voltages, for each two states of voltages there is a predefined output according to complement rule.
- 3. Apparatus used Npn transistor (547 b) Circuit board Wires 9V battery and battery connector LED (5mm, 1.5V) Resistors Push button type toggle switch Push buttons
- 4. Theory and working 1.)Working of npn transistor in different configurations
- 5. 2.)Understanding the functioning of NOT gate and its realisation
- 7. Realisation of NOT gate
- 8. 3.)Circuit diagram used in making of NOT gate and its working For first circuit When the push button is in ‘released state’ then terminal ‘2’ is connected to terminal ‘3’, when push button is in ‘active or pressed’ then terminal ‘2’ is connected to terminal ‘1’.
- 9. When button is released then it is equivalent to zero base current. In this state, transistor is in cut-off mode no current flows through transistor, so whole current flows through LED. When button is pressed then it is equivalent to high base current. In this state, transistor is in saturation mode, maximum current flows through transistor to negative of battery but does not flows through LED.
- 10. Conclusion The output of NOT gate for different inputs clearly shows the expected output according to the truth table. Sources of errors Write yourself Precautions Do not connect any electronic component without resistance in series, it can burn the component. Bibliography NCERT textbook of class 12 Physics by S.L.Arora Circuits available on internet