Noise immune transmission gate
AssigneeSun Microsystems, Inc.
InventorsSudhakar Bobba, Pradeep Trivedi
Life of this patent
Estimating the term…
Abstract
A transmission gate immune to noise that selectively delivers/draws charge to/from a noisy input node in order to ensure that an output node is not adversely affected by the noise on the input node is provided. Further, an NMOS pass gate immune to noise that delivers charge to a noisy input node in order to ensure that an output node is not adversely affected by the noise on the input node is provided. Further, a PMOS pass gate immune to noise that draws charge from a noisy input node in order to ensure that an output node is not adversely affected by the noise on the input node is provided.
Claims17
An integrated circuit having a transmission gate that selectively controls passage of a signal from a first node to a second node, the transmission gate comprising:
- a first stage that provides a low impedance path between the first node and the second node when the transmission gate is enabled, the first stage comprising:
- a current sourcing device that delivers charge to the first node when the transmission gate is disabled and a voltage of the first node goes below a first critical voltage;
- and
- a second stage that provides a low impedance path between the first node and the second node when the transmission gate is enabled, the second stage comprising:
- a current sinking device that draws charge from the first node when the transmission gate is disabled and the voltage of the first node goes above a second critical voltage.
An integrated circuit having a transmission gate that selectively controls passage of a signal from a first node to a second node, the transmission gate comprising:
- a first pass means for providing a low impedance path between the first node and the second node when the transmission gate is enabled, the first pass means comprising:
- a charge delivering means for delivering charge to the first node when the transmission gate is disabled and a voltage of the first node goes below a first critical voltage;
- and
- a second pass means for providing a low impedance path between the first node and the second node when the transmission gate is enabled, the second pass means comprising:
- a charge drawing means for drawing charge from the first node when the transmission gate is disabled and the voltage of the first node goes above a second critical voltage.
A method for performing circuit operations using a transmission gate that selectively controls passage of a signal from a first node to a second node, the method comprising the steps of:
- facilitating the passage of the signal from the first node to the second node when the transmission gate is enabled by a control signal;
- sourcing current to the first node when the transmission gate is disabled by the control signal and a voltage of the first node goes below a first critical voltage;
- and
- sinking current from the first node when the transmission gate is disabled by the control signal and the voltage of the first node goes above a second critical voltage.
Dependencies are inferred from the claim text.