NOT circuit application circuit design diagram
INDUSTRIAL LCD DISPLAYS / IGBT MODULES DISTRIBUTOR

Infineon / Mitsubishi / Fuji / Semikron / Eupec / IXYS

# NOT circuit application circuit design diagram

Posted Date: 2024-02-05

What is a logic circuit

Digital circuits perform logical operations and are also called logic circuits. There are only three basic elements of logic circuits: AND circuit, OR circuit and NOT circuit. Circuits with various functions can be made by different combinations of these three logic circuits.

Logic circuits are represented using logical expressions and circuit symbols (MIL symbols are used here, and JIS symbols are used in others). In addition, we call the list of input signals and output signals of a logic circuit a truth table.

The NOT circuit is also called a frequency conversion or reverse circuit and has the function of inverting the input to output. It is a circuit that outputs 0 when the input is 1, and outputs 1 when the input is 0. Logical expressions are represented by "¯" (for example) Y=.

The application circuit diagram is shown in Figure (a): it is a NOT circuit composed of ordinary triodes. Here, 5 volts is the high level H, and 0 volts is the low level L. When switch A is connected to L, the transistor is turned off, and no current flows through the resistor RC, so there is no voltage drop, and the voltmeter indicates 5 volts. When switch A is connected to H, the base voltage of the transistor rises, the collector is turned on, and current passes through the resistor RC, resulting in a voltage drop. The indication of the voltmeter X is 0 volts, which is the output L.

When A is connected to H, the base of the transistor is at a high level, and the transistor is saturated. Then the 5 volt voltage at the other end passes through the resistor RC, the collector and the emitter, forming a loop. The resistance between collector and emitter is very small. It must not be as large as the resistance of light bulb X. The light bulb will not light up.

When A is connected to L, the base of the transistor is connected to negative electricity, and the transistor is cut off. At this time, an open circuit is formed between the collector and the emitter, and the 5 volt voltage at the other end passes through the resistor RC and the light bulb X, forming a loop. The light bulb will light up.

What is the difference between the NOT gate of analog circuits and the NOT gate of digital circuits?

There are some differences in the implementation and application of the NOT gate of analog circuits and the NOT gate of digital circuits.

The NOT gate of analog circuits is usually implemented with an operational amplifier, and its inverting amplification characteristics are used to implement the NOT operation of the signal. The NOT gate of a digital circuit is usually implemented using a transistor, and the switching characteristics of the transistor are used to implement the NOT operation of the signal.

The NOT gate of analog circuits is mainly used for signal amplification and transmission to amplify or reduce the input signal to meet the needs of subsequent circuits. The NOT gate of digital circuits is mainly used to implement logical operations and control, and is one of the basic units of digital circuits.

The NOT gate of an analog circuit usually has only one input and one output, while the NOT gate of a digital circuit can have multiple inputs and outputs so that it can be combined with other logic gates to achieve more complex logic operations and circuit control.

Although there are differences in implementation and application between the NOT gate of analog circuits and the NOT gate of digital circuits, their core functions are to implement the NOT operation of signals, but the application scenarios and implementation methods are slightly different.

Review Editor: Huang Fei

#circuit #application #circuit #design #diagram