Thursday, July 30, 2009

US Patent 7567414 - Nanotube electrostatic discharge protection circuit

One key advantage of carbon nanotubes to electronics is their ability to withstand current densities greater than 100 times that of copper. This patent from Nantero takes advantage of this property in forming an electrostatic discharge protection circuit. Claim 1 reads:

1. An electrostatic discharge (ESD) protection circuit for protecting a protected circuit coupled to an input pad from an ESD-induced voltage of positive or negative polarity, comprising:

a nanotube switch having at least two terminals coupled to the protected circuit and to a single discharge path;

wherein the nanotube switch, in response to the ESD-induced voltage, switches between a de-activated state and an activated state;

wherein the activated state creates a current path in either direction between the at least two terminals, so that a signal on the input pad flows to or from the single discharge path to cause the signal at the input pad to remain within a predefined operable range for the protected circuit, wherein the nanotube switch returns to the de-activated state after the duration of the ESD-induced voltage.