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jusaca
jusaca
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You make the common, and mistaken, assumption that a node that is not actively driven (has zero current flowing) must be at a low voltage. That is not true.

The output of the gate must be pulled down or it can not operate reliably. Without a pull down of some kind the output voltage is indeterminate. You could use a resistor pulldown but that will waste a lot of power and/or be slower than an NMOS pulldown.

You make the common, and mistaken, assumption that a node that is actively driven (has zero current flowing) must be at a low voltage. That is not true.

The output of the gate must be pulled down or it can not operate reliably. Without a pull down of some kind the output voltage is indeterminate. You could use a resistor pulldown but that will waste a lot of power and/or be slower than an NMOS pulldown.

You make the common, and mistaken, assumption that a node that is not actively driven (has zero current flowing) must be at a low voltage. That is not true.

The output of the gate must be pulled down or it can not operate reliably. Without a pull down of some kind the output voltage is indeterminate. You could use a resistor pulldown but that will waste a lot of power and/or be slower than an NMOS pulldown.

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Elliot Alderson
Elliot Alderson
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You make the common, and mistaken, assumption that a node that is actively driven (has zero current flowing) must be at a low voltage. That is not true.

The output of the gate must be pulled down or it can not operate reliably. Without a pull down of some kind the output voltage is indeterminate. You could use a resistor pulldown but that will waste a lot of power and/or be slower than an NMOS pulldown.