Abstract: Oscillator circuitry having a switching inverting amplifier arranged in a ring oscillator configuration of at least two stages. A bias generator for supplying the amplifiers of neighboring stages, is responsive to an enable signal to supply the amplifiers only when the enable signal is asserted. A first pair of transistors, coupled to an input of one of the amplifiers and the other coupled to an output of the amplifier, the transistors being driven in common by the enable signal such that when the enable signal is deasserted the transistors of the pair are turned on to impose conflicting levels at the input and the output such that the amplifier is forced to switch.

Abstract: Oscillator circuitry having a switching inverting amplifier arranged in a ring oscillator configuration of at least two stages. A bias generator for supplying the amplifiers of neighboring stages, is responsive to an enable signal to supply the amplifiers only when the enable signal is asserted. A first pair of transistors, coupled to an input of one of the amplifiers and the other coupled to an output of the amplifier, the transistors being driven in common by the enable signal such that when the enable signal is deasserted the transistors of the pair are turned on to impose conflicting levels at the input and the output such that the amplifier is forced to switch.

Abstract: A system and method are disclosed to limit a maximum duty cycle and/or provide a volt-second clamp for a pulse-width modulated (PWM) signal. Depending on the circuit topology, this approach can limit the absolute duty cycle or operate as a volt-second clamp in which the duty cycle is limited as a function of a variable input control voltage, such as a line voltage. The duty cycle can be selectively programmed by setting one or more external reference components, such as one or more respective resistors. Additionally, through component matching, desired clamping can be achieved with a high level of accuracy.

Abstract: A battery protection circuit includes a moisture detection circuit, a temperature sensing circuit, and a high-temperature battery discharge circuit. The moisture detection circuit includes a pair of conductive traces closely spaced on a substrate such that a resistive path is formed between the traces when moisture forms on the substrate. The traces are connected between the positive battery terminal and a pull-down current source. When moisture forms on the substrate, pull-up current flows between the traces, and a resulting voltage change on one of the traces is detected by circuit element such as a logic inverter. The temperature sensing circuit includes a voltage reference circuit that generates a proportional-to-temperature voltage and temperature-independent voltage reference signals corresponding to various predetermined temperatures.

Abstract: According to one embodiment of the invention, method of manufacturing a metal-oxide-semiconductor transistor structure includes forming dielectric isolation regions in a semiconductor substrate, forming a first dielectric layer outwardly from the semiconductor substrate, forming a polysilicon layer outwardly from the first dielectric layer, etching a portion of the polysilicon layer to form a gate, and forming at least one notch in a first side of the gate. The method further includes etching a portion of the first dielectric layer to expose the semiconductor substrate, forming an n+ source region in the semiconductor substrate adjacent the first side of the gate, forming an n+ drain region in the semiconductor substrate adjacent a second side of the gate, and forming at least one p+ substrate contact region proximate the notch and adjacent the n+ source region.

Abstract: An electronic device includes a conductive member disposed within an insulative package. The conductive member is formed from a lead frame used to form the interconnection pins for the device. The conductive member includes an elongated, folded sense element portion having a known resistance. The sense element portion is disposed between two sets of conductive lead portions extending from the conductive member forming pins used to provide a current to the device for sensing. An integrated circuit disposed within the package includes a differential amplifier having differential inputs connected to bond pads on the integrated circuit. The bond pads are connected to spaced-apart tap points of the sense element via conductive bond wires, so that the combination of the sense element and the differential amplifier forms a trans-impedance amplifier. The gain of the differential amplifier is controlled to be proportional to the magnitude of a reference voltage generated by a bandgap voltage reference circuit.

Abstract: A battery protector for providing overvoltage and undervoltage protection to one or more series-connected cells. The battery protector includes a voltage detection and comparison circuit, providing an overvoltage signal indicative of whether the voltage across any of the cells is greater than an overvoltage threshold level and an undervoltage signal indicative of whether the voltage across any of the cells is less than an undervoltage threshold level, and a switch connected in series with the current path between the cells and a charger and/or load. In one embodiment, the switch is a four-terminal FET and a bias control circuit is provided for selectively connecting the body region of the FET to ensure that current does not flow through the parasitic FET diodes.

Abstract: A pulse width modulator voltage feedforward circuit which includes a gating circuit for providing a control signal to a charge circuit which charges an integration circuit with a current proportional to an input voltage. The integration circuit provides an output ramp signal waveform having a slope proportional to the input voltage value. The gating circuit also provide a control signal to a discharge circuit, to thus alternately charge and discharge the integration circuit. The gating circuit insures that a minimum deadtime for a transformer reset will occur regardless of input voltage variations by preventing a fixed frequency signal provided by an oscillator from beginning a new ramp waveform signal period until the integration circuit is discharged to a minimum reference voltage level.