E6C10
CIRCUIT COMPONENTS · Digital ICs: families of digital ICs; gates; programmable logic devices
E6C10E6C →
In Figure E6-3, which is the schematic symbol for a NOR gate?
- A1
- B2
- C3
- D4
Why A NOR gate is an OR gate followed by an inversion, so its symbol is the OR shape, a body with a concave curved back and a pointed, bullet-like nose, with a small inversion bubble on the output. The bubble is what makes it NOR rather than plain OR: the output is low whenever any input is high, and high only when all inputs are low. In Figure E6-3 that pointed-nose-plus-bubble symbol is the one numbered 4.
Watch out The most tempting mistake is the NAND symbol, which also has an output bubble but uses the AND body: a flat back and a smooth semicircular (D-shaped) front instead of the pointed OR nose.
Bubble on the output = NOT. D-shape = AND, pointed nose = OR. Pointed nose + bubble = NOR.
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
The rest of E6C
- E6C01 What is the function of hysteresis in a comparator?
- E6C02 What happens when the level of a comparator's input signal crosses the threshold voltage?
- E6C03 What is tri-state logic?
- E6C04 Which of the following is an advantage of BiCMOS logic?
- E6C05 Which of the following digital logic families has the lowest power consumption?
- E6C06 Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?
- E6C07 What best describes a pull-up or pull-down resistor?
- E6C08 In Figure E6-3, which is the schematic symbol for a NAND gate?
- E6C09 What is used to design the configuration of a field-programmable gate array (FPGA)?
- E6C10 In Figure E6-3, which is the schematic symbol for a NOR gate?
- E6C11 In Figure E6-3, which is the schematic symbol for the NOT operation (inversion)?