Nanotube ESD protective devices and corresponding nonvolatile and volatile
nanotube switches. An electrostatic discharge (ESD) protection circuit
for protecting a protected circuit is coupled to an input pad. The ESD
circuit includes a nanotube switch electrically having a control. The
switch is coupled to the protected circuit and to a discharge path. The
nanotube switch is controllable, in response to electrical stimulation of
the control, between a de-activated state and an activated state. The
activated state creates a current path so that a signal on the input pad
flows to the discharge path to cause the signal at the input pad to
remain within a predefined operable range for the protected circuit. The
nanotube switch, the input pad, and the protected circuit may be on a
semiconductor chip. The nanotube switch may be on a chip carrier. The
deactivated and activated states may be volatile or non-volatile
depending on the embodiment. The ESD circuit may be repeatedly programmed
between the activated and deactivated states so as to repeatedly activate
and deactivate ESD protection of the protected circuit. The nanotube
switch provides protection based on the magnitude of the signal on the
input pad.