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E6C06
Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?
Pick an answer to check it.
Answer: C. The input switching threshold is about half the power supply voltage
A CMOS input switches at about half the supply voltage, right in the middle. Noise must swing a large amount to falsely cross that threshold, giving good noise immunity.
Tip: CMOS threshold at half supply.