Picor Corporation

Semiconductor Components Industries, LLC

Cherry Semiconductor Corporation

Jeffrey Gordon Dumas

Michael A Briere

Patrizio Vinciarelli

Christopher John Sanzo

Benjamin M Rice

Bishara Tahhan

Stephen Saunders Yole

Techniques for adjusting the voltage across an active filter element include a controlled circuit element and a control circuit element adapted to control the voltage across the controlled circuit element to increase transient load response and to reduce power dissipation.

Active filtering

Techniques for reducing noise generated by a circuit include a common mode filter and a differential mode filter. The common mode filter includes an input for sensing a common mode signal between a power source and the circuit, an output, and active circuitry for producing an offset signal on the output. The differential mode filter includes an input, an output, and active circuitry for sensing a differential mode signal and producing variations in resistance between the input and output to offset the differential signal.

EMI filter circuit

A method of forming a power supply timing controller circuit ( ) includes forming a bi-directional synchronization oscillator controller ( ) to oscillate at an internal frequency. The bi-directional synchronization oscillator controller ( ) receives an external sync signal, suspends the oscillation, begins operating at the forced frequency of the external sync signal, and begins a delay period. If another external sync signal is not received before the end of the delay period, the controller resets and once again begins oscillating at the internal frequency.

Method of forming a bi-directional synchronization controller

A sharp transition is achieved between pushing and pulling an output current by simultaneously diverting the bias current from a series stacked transistor circuit and from the base of a sink transistor. After the series stacked transistor circuit is kept from conducting output current, the sink transistor allows bias current to drive the other transistor circuit in the stack. Each of the transistor circuits in the stack is associated with a bias current and a sink transistor. The sink transistors and the bottom transistor circuit in the stack have emitters coupled to a floating ground. A switching signal input circuit includes an input transistor and a current mirror. The low input signal from the switching signal input circuit to a control input at a first sink transistor in the drive circuit is clamped relative to the floating ground.

Sharp transition push-pull drive circuit with switching signal input circuit

A high speed totem pole FET driver circuit with differential cross-conduction prevention. The driver circuit includes first and second switching elements coupled to a first node, and third and fourth switching elements coupled to a second node. The first node is coupled to a first current source, a pulldown circuit, and the input of the third switching element. The second node is coupled to a second current source, a pullup circuit, and the input of the second switching element. Trigger inputs are applied to the inputs of the first and fourth switching elements to switch the first and fourth switches ON and OFF, wherein the two trigger inputs are of opposite phase so that when one input is HIGH (LOW) the other input is LOW (HIGH). The second switching element may include a comparator circuit with its non-inverting input coupled to the second node, its inverting input coupled to a power source via a V.sub.BE circuit, and its output coupled to a fifth switching element, where the fifth switching element is coupled to the first node.

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West Warwick, RI, United States of America

Jeffrey Gordon Dumas