Abstract: Embodiments of neural interfaces according to the present invention comprise sensor modules for sensing environmental attributes beyond the natural sensory capability of a subject, and communicating the attributes wirelessly to an external (ex-vivo) portable module attached to the subject. The ex-vivo module encodes and communicates the attributes via a transcutaneous inductively coupled link to an internal (in-vivo) module implanted within the subject. The in-vivo module converts the attribute information into electrical neural stimuli that are delivered to a peripheral nerve bundle within the subject, via an implanted electrode. Methods and apparatus according to the invention incorporate implantable batteries to power the in-vivo module allowing for transcutaneous bidirectional communication of low voltage (e.g. on the order of 5 volts) encoded signals as stimuli commands and neural responses, in a robust, low-error rate, communication channel with minimal effects to the subjects' skin.

Abstract: Embodiments of neural interfaces according to the present invention comprise sensor modules for sensing environmental attributes beyond the natural sensory capability of a subject, and communicating the attributes wirelessly to an external (ex-vivo) portable module attached to the subject. The ex-vivo module encodes and communicates the attributes via a transcutaneous inductively coupled link to an internal (in-vivo) module implanted within the subject. The in-vivo module converts the attribute information into electrical neural stimuli that are delivered to a peripheral nerve bundle within the subject, via an implanted electrode. Methods and apparatus according to the invention incorporate implantable batteries to power the in-vivo module allowing for transcutaneous bidirectional communication of low voltage (e.g. on the order of 5 volts) encoded signals as stimuli commands and neural responses, in a robust, low-error rate, communication channel with minimal effects to the subjects' skin.

Abstract: A microelectromechanical (MEM) filter is disclosed which has a plurality of lattice networks formed on a substrate and electrically connected together in parallel. Each lattice network has a series resonant frequency and a shunt resonant frequency provided by one or more contour-mode resonators in the lattice network. Different types of contour-mode resonators including single input, single output resonators, differential resonators, balun resonators, and ring resonators can be used in MEM filter. The MEM filter can have a center frequency in the range of 10 MHz-10 GHz, with a filter bandwidth of up to about 1% when all of the lattice networks have the same series resonant frequency and the same shunt resonant frequency. The filter bandwidth can be increased up to about 5% by using unique series and shunt resonant frequencies for the lattice networks.

Abstract: The present invention is a method for reducing phase noise in oscillator signals. For example, the oscillator may be a low phase noise MEMS-based oscillator and may include a resonator (ex.—a MEMS resonator). Further, the resonator of the oscillator may be operated near a bifurcation point. Still further, the MEMS resonator may be parametrically pumped in such a way so as to redistribute the quadrature signal noise (ex.—phase noise) to in-phase noise (ex.—amplitude noise).

Abstract: A method is disclosed which calculates dimensions for a MEM resonator in terms of integer multiples of a grid width G for reticles used to fabricate the resonator, including an actual sub-width La=NG and an effective electrode width We=MG where N and M are integers which minimize a frequency error fe=fd?fa between a desired resonant frequency fd and an actual resonant frequency fa. The method can also be used to calculate an overall width Wo for the MEM resonator, and an effective electrode length Le which provides a desired motional impedance for the MEM resonator. The MEM resonator can then be fabricated using these values for La, We, Wo and Le. The method can also be applied to a number j of MEM resonators formed on a common substrate.

Abstract: Parasitic feed-through capacitance effects in a resonator circuit are reduced by separating the resonator signal from the feed-through capacitance signal and then detecting the resonator signal with comparator circuitry. In specific embodiments, the separation of the resonator signal from the feed-through capacitance signal is effected by serial integrator and differentiator circuitry or by trans-impedance amplifier circuitry. The comparator circuitry can include control/delay circuitry for enabling the comparator at a correct time when feed-through capacitance signal has dissipated. The invention can be implemented using microelectromechanical sensors (MEMS) in a strain gauge function.

Abstract: A charge pump having an output diode with a zero voltage drop. The present charge pump may be a multiple stage charge pump that may operate more efficiently than prior charge pumps by substantially removing the voltage drop across the output diode. The last stage in the charge pump receives a second input clock signal. The output diode includes a switch device coupled to a bootstrapping circuit which receives a third input clock signal and a fourth input clock signal. The third input clock signal and the fourth input clock signal are either non-overlapping high clock signals or non-overlapping low clock signals. A specified relationship between the second clock signal and the third clock signal, and a specified relationship between the third clock signal and the fourth clock signal are required to allow the bootstrapping circuit to properly augment the voltage passed through the switch device in the output diode.

Abstract: A zero voltage drop switch in a negative switch circuit. The zero voltage drop switch substantially passes the entire negative voltage signal provided by a negative voltage source to the output of the negative switch circuit. The zero voltage drop switch includes a switch circuit coupled to a bootstrapping circuit which augments the voltage passed by the switch circuit. The bootstrapping circuit includes a pair of capacitive devices that receive a pair of non-overlapping clock signals.

Abstract: A voltage detector circuit. The voltage detector circuit determines when a supply voltage exceeds a predetermined threshold voltage. According to one embodiment, the voltage detector circuit is used in a nonvolatile memory device to determine whether a programming supply voltage is five volts or twelve volts.

Abstract: A voltage detector circuit for detecting when an input voltage exceeds a trip-point voltage. The voltage detector circuit includes a nonvolatile memory cell having a select gate coupled to the input voltage, a drain coupled to a first node, a source coupled to system ground, and a floating gate. The nonvolatile memory cell is used primarily as a pull-down transistor, and the threshold voltage of nonvolatile memory is programmed to be the trip-point voltage such that the first node is set to system ground if the input voltage exceeds the trip-point voltage. The voltage detector circuit also includes a first transistor having a control electrode coupled to a biasing voltage, a first terminal coupled to the first node, and a second terminal coupled to a supply voltage. The control electrode is operative to couple the first terminal to the second terminal in response to the biasing voltage. The first transistor sets the first node to the input voltage if the input voltage is less than the trip-point voltage.