1
Winthrop H McClure, John A O Connor, Robert A Mammano: Voltage sensor for detecting cell voltages. Unitrode Corporation, Weingarten Schurgin Gagnebin & Hayes, July 29, 1997: US05652501 (174 worldwide citation)

A battery charger/monitor circuit for charging and/or monitoring a plurality of series-connected cells, including a voltage sensor for sensing the voltage across each of the cells to provide a high cell voltage signal proportional to the highest voltage across any of the cells and a low cell voltage ...


2
John P Bazinet, John A O Connor: DC/DC converter having a bootstrapped high side driver. Unitrode Corporation, Weingarten Schurgin Gagnebin & Hayes, May 6, 1997: US05627460 (152 worldwide citation)

A synchronous step-down DC to DC converter includes a bootstrap capacitor monitored by a controller for maintaining a desired bootstrap voltage to drive a high side NMOS switch. The controller temporarily increases the duty cycle of the low side NMOS switch when the bootstrap voltage decreases below ...


3
Jimmy Aubrey Walker: Apparatus and method for generating a low frequency AC signal. Unitrode Corporation, Weingarten Schurgin Gagnebin & Hayes, September 2, 1997: US05663878 (90 worldwide citation)

An apparatus and method for generating a low frequency AC signal such as a ringing voltage signal for a telephone subscriber interface unit or the like. The apparatus comprises an oscillator which drives a pair of counters whose outputs differ by a desired low frequency. The output of the first coun ...


4
Raoji Patel: Synchronous power rectifier. Unitrode Corporation, Weingarten Schurgin Gagnebin & Hayes, December 29, 1987: US04716514 (62 worldwide citation)

A synchronous power rectifier incorporating a bipolar power transistor operable in a switching mode to rectify the energy from a secondary winding of a power transformer. The synchronous rectifier reduces or eliminates the need of rectifier diodes, which provides power rectification without the powe ...


5
Burt L Price: Multi-cell battery pack charge balancing circuit. Unitrode Corporation, Weingarten Schurgin Gagnebin & Hayes, September 5, 2000: US06114835 (62 worldwide citation)

A charge balancing circuit incorporates a voltage threshold which determines when to initiate a charge balance mode in order to equalize the level of charge in at least two cells of a multi-cell battery pack. Charge balancing is initiated when the voltage level of a first cell reaches this second th ...


6
Mark Jordan, Robert A Mammano: Load current sharing circuit. Unitrode Corporation, Weingarten Schurgin Gagnebin & Hayes, October 20, 1992: US05157269 (61 worldwide citation)

A load current sharing circuit is disclosed that allows multiple independent power modules, either switching or linear, to be connected in a parallel configuration such that each module delivers only its proportionate share of the load current. Each module measures the common output voltage, compare ...


7
Claudio de Sa e Silva, Jeffrey D Putsch, Varnum S Holland, Wilburn M Miller: Transformer isolated drive circuit. Unitrode Corporation, Weingarten Schurgin Gagnebin & Hayes, April 27, 1993: US05206540 (59 worldwide citation)

A transformer isolated circuit for driving a semiconductor power switch includes a transformer which is driven with a high frequency Pulse Width Modulated (PWM) signal in such a way that the constantly present PWM carrier supplies the power needed for high gate current pulses, while different duty c ...


8
Robert A Mammano, John A O Connor: Switching regulator with improved Dynamic response. Unitrode Corporation, Weingarten Schurgin Gagnebin & Hayes, June 6, 1995: US05422562 (57 worldwide citation)

A switching regulator having improved dynamic response to load variations includes a load compensation circuit coupled to the output terminal. The load compensation circuit supplies current to a load coupled to the output terminal when the output voltage is less than a first predetermined level and/ ...


9
Robert A Mammano, Larry Wofford, Winthrop H McClure, Burt L Price: Battery protector. Unitrode Corporation, Weingarten Schurgin Gagnebin & Hayes, December 3, 1996: US05581170 (56 worldwide citation)

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 ove ...


10
Burt L Price: Bandgap voltage reference based temperature compensation circuit. Unitrode Corporation, Weingarten Schurgin Gagnebin & Hayes, June 16, 1998: US05767664 (56 worldwide citation)

A voltage-to-current converter for use with a bandgap voltage reference circuit for providing a correction current to compensate for the adverse effects of temperature. In one specific embodiment, the voltage-to-current converter is used to provide output voltage curvature correction to the resident ...