Abstract: A semiconductor device suitable for use in a pressure sensor is disclosed. A uniformly thin die is provided by chemically etching a back side of a wafer. Piezoelectric elements formed integrally within the die generate electrical signals in response to flexing the die. Conductive leads formed integrally within the die electrically communicate the generated electrical signals to support circuitry formed integrally within the die proximate the piezoelectric elements. In an example embodiment, the piezoresistive elements take the form of silicon resistors formed integrally via doping and diffusion in a Wheatstone bridge configuration. In one application, the die serves as a deformable diaphragm, seated atop an aperture of a threaded pressure sensor housing.

Abstract: A semiconductor device suitable for use in a pressure sensor is disclosed. A uniformly thin die is provided by chemically etching a backside of a wafer. Piezoelectric elements formed integrally within the die generate electrical signals in response to flexing the die. Conductive leads formed integrally within the die electrically communicate the generated electrical signals to support circuitry formed integrally within the die proximate the piezoelectric elements. In an example embodiment, the piezoresistive elements take the form of silicon resistors formed integrally via doping and diffusion in a Wheatstone bridge configuration. In one application, the die serves as a deformable diaphragm, seated atop an aperture of a threaded pressure sensor housing.

Abstract: The formation of a semiconductor sensing device is disclosed, where the device can be used to sense pressure, for example. The device is formed by etching the entire backside of a semiconductor substrate or wafer. This streamlines the fabrication process by omitting a number of steps that would otherwise be required to selectively etch certain locations of the substrate. This also improves device performance and compactness by allowing associated support circuitry to be formed closer to a sensing region, and more particularly piezoelectric elements of the sensing region.

Abstract: Systems and methods are provided for providing precision timing signals. A first register bank, driven by a first clock signal, provides a first delay along a first signal path. A second register bank, driven by a second clock signal related to the first clock signal, provides a second delay along a second signal path. A system control controls at least one of the first and second banks of registers to control the first and second delays, as to provide a desired skew between the output of the first signal path and the second signal path.

Abstract: A deglitch circuit utilizes a first flip-flop coupled to the input signal and a second flip-flop coupled to the output of a circuit with feedback from the output to gates to control first and second inputs to the first flip-flop. In an alternative arrangement, a counter is provided between the output of the first flip-flop and the input to the second flip-flop in order to provide flexibility and the possibility of a longer delay for the circuit.

Abstract: The present invention relates to a reverse bias protection structure which comprises a PMOS transistor structure having a drain portion, a gate portion, a source portion and a backgate portion, wherein the gate portion is coupled to a first voltage potential, the source portion is selectively coupleable to a power supply, and the drain portion is selectively coupleable to a circuit needing power to be supplied thereto from the power supply. The reverse bias protection structure further comprises a Schottky diode structure having an anode coupled to the source portion of the PMOS transistor structure, and a cathode coupled to the backgate portion of the PMOS structure. Under forward bias conditions, the PMOS transistor conducts and exhibits a small voltage drop thereacross. Under reverse bias conditions, the PMOS transistor is off and the Schottky structure is reverse biased, thus preventing current through the protection structure.

Abstract: The present invention relates to a motor drive system which comprises a fan controller circuit operable to generate a PWM control signal for control of a motor speed. The fan controller circuit comprises a current detection circuit and a motor speed determination circuit. The system further comprises a fan driver circuit operable to drive a motor at a duty cycle based on the PWM control signal from the fan controller circuit. The fan driver circuit comprises a current sink circuit operable to draw current from the PWM control signal when the PWM control signal is high and when the motor reaches a predetermined position. In the addition, the current detection circuit is operable to detect the current draw on the PWM control signal and provide an indication signal to the fan speed determination circuit associated with such detection. Further, the motor speed determination circuit is operable to determine the speed of the motor based upon a timing associated with successive current draw detections.

Abstract: The present invention relates to a reverse bias protection structure which comprises a PMOS transistor structure having a drain portion, a gate portion, a source portion and a backgate portion, wherein the gate portion is coupled to a first voltage potential, the source portion is selectively coupleable to a power supply, and the drain portion is selectively coupleable to a circuit needing power to be supplied thereto from the power supply. The reverse bias protection structure further comprises a Schottky diode structure having an anode coupled to the source portion of the PMOS transistor structure, and a cathode coupled to the backgate portion of the PMOS structure. Under forward bias conditions, the PMOS transistor conducts and exhibits a small voltage drop thereacross. Under reverse bias conditions, the PMOS transistor is off and the Schottky structure is reverse biased, thus preventing current through the protection structure.

Abstract: The present invention relates to a motor drive system which comprises a fan controller circuit operable to generate a PWM control signal for control of a motor speed. The fan controller circuit comprises a current detection circuit and a motor speed determination circuit. The system further comprises a fan driver circuit operable to drive a motor at a duty cycle based on the PWM control signal from the fan controller circuit. The fan driver circuit comprises a current sink circuit operable to draw current from the PWM control signal when the PWM control signal is high and when the motor reaches a predetermined position. In the addition, the current detection circuit is operable to detect the current draw on the PWM control signal and provide an indication signal to the fan speed determination circuit associated with such detection. Further, the motor speed determination circuit is operable to determine the speed of the motor based upon a timing associated with successive current draw detections.