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What are the three fundamental logic gates?
All digital systems can be constructed by only three basic logic gates. These basic gates are called the AND gate, the OR gate, and the NOT gate. Some textbooks also include the NAND gate, the NOR gate and the EOR gate as the members of the family of basic logic gates.
Which of the following gate will give a 0 when both of its inputs are 1?
Which of the following gate will give a 0 when both of its inputs are 1? Explanation: The NAND gate gives 0 as the output when both of its inputs are 1 or any one of the input is 1.
How does a pull up resistor work in a logic gate?
With a pull-up resistor connected, the output still works in the same way as a normal logic gate in that when the output transistor is OFF (open), the output is HIGH, and when the transistor is ON (closed), the output is LOW. Thus the transistor turns ON to pull the output to a LOW level.
How are logic high and low represented in a gate?
The simple OR gate designed by two diodes is shown in the below figure. Inputs are given to this circuit by the two diodes. In this, the logic HIGH (1) is represented by +5 Volts and logic LOW (0) is represented by 0 Volts or Ground. In the circuit below, the two inputs are left unconnected, so the output is 0 i.e. logic low.
How are logic gates designed to receive binary data?
Some logic gates like NOT gate or Inverter has only one input and one output. The inputs of the logic gates are designed to receive only binary data (only low 0 or high 1) by receiving the voltage input. The low logic level represents Zero volts and high logic level represents 3 or 5 volts positive supply voltage.
When does the current flow out of the logic gate?
Likewise, when the input of the logic gate is LOW, the current flows out of the TTL input as the input acts basically as a path connected directly to Vcc. This input current, I IL (max) is negative in value as it flows “out-of” the gate and for most TTL 74LSxxx inputs, has a value of -400μA, (-0.4mA).