Semiconductor Components Industries, LLC

Astec International Limited

Analog Devices,inc.

Intersil Americas Inc.

Marc E Dagan

Zhiwei Liu

Xudong Huang

Carl K Sawtell

Kaiwei Yao

Ruchi Parikh

David Anthony Smith

Sergei Slavnov

Frederic S Bandy

An adaptive gate driver for a driving a power MOSFET to switch is disclosed. The adaptive gate driver includes a load sense circuit to sense a current through the power MOSFET. A controller coupled to the load sense circuit compares the sensed current to a threshold to determine if the load on the power MOSFET is a normal load or a heavy load. Based on the comparison, the controller controls the gate driver to drive the power MOSFET with a first strength level when a normal load determined and at second strength level when a heavy load is determined. The driving strength in the heavy-load condition is lower than the normal-load condition and by lowering the driving strength of the gate driver during the heavy-load condition a voltage across the power MOSFET may be prevented from exceeding a threshold related to a breakdown condition during a switching period.

Adaptive gate driver

The present disclosure describes a power stage. The power stage includes a metal-oxide semiconductor field-effect transistor (MOSFET) and a driver IC coupled to the MOSFET. The driver IC is configured to switch the MOSFET to an ON-state so that MOSFET conducts a current. The driver IC includes a current monitor circuit that outputs a current monitor signal, which corresponds to the current through the MOSFET when it is in the ON-state. The current monitor signal includes an error caused by a temperature difference between the MOSFET and the driver IC. As a result, the driver IC further includes a compensation circuit that is configured to determine a thermal gradient across the driver IC, and based on the thermal gradient, adjust the current monitor circuit to reduce the error.

Thermal gradient correction of a current monitor signal

In an embodiment, a power-supply controller includes a switching regulator and a current limiter. The switching regulator is configured to generate an input current such that an output voltage is generated in response to the input current and an input voltage, and the current limiter is configured to limit the input current in response to a quantity that is related to a ratio of the output voltage divided by the input voltage. For example, an embodiment of such a power-supply controller may be able to limit the output or load current from a power supply to a set level by limiting the input current in response to a quantity that is related to the ratio (e.g., the boost ratio) of the output voltage to the input voltage.

Limiting a current

A system and method for battery isolation in a charging system includes an isolation diode connected to a charger input voltage and a PNP pass transistor connected in series between the isolation diode and a battery. The pass device conducts a charging current in response to a drive signal applied to its base; the pass transistor side of the diode is at a voltage V . A first switch couples the pass transistor's base to V when V >V such that the pass transistor's base-collector junction blocks current from V from flowing through the pass transistor when the charger is not in use, and a second switch couples the base to V when V >V such that the pass transistor's base-emitter junction blocks current from the battery from flowing through the pass transistor when the charger is not in use.

System and method for battery isolation in a charging system

A circuit for controlling the switching behavior of a field effect transistor (FET) or other power switch in a power supply or converter. The circuit includes an adaptive feedback loop which controls the switching operation of the FET through application of a gate drive signal to the device. The circuit is designed to turn the switching device on or off at the optimum time to reduce the stress and power losses associated with the switching action. The circuit includes a capacitor connected to the FET switch drain to sense the falling voltage across the switch. The adaptive gate drive circuit holds the FET switch off until the drain voltage sensed by the capacitor stops decreasing. At this time, the FET switch voltage is either zero (zero-voltage switching) or has reached the minimum value of its resonant ring (low-voltage switching). The gate drive circuit then turns the FET switch on, initiating a new cycle of charging up the inductor or primary transformer winding which is part of the power supply or converter. The present invention, thus acts, to minimize switching stress and power loss during the switching cycle.

Adaptive drive circuit for zero-voltage and low-voltage switches

A programmable temperature detector for simple detection applications is described. The programmable temperature detector has three terminals and a plurality of temperature-transitions points from which to choose. A first terminal receives power from a supply, a second terminal receives a ground reference, and a third terminal provides an indication of an object's temperature crossing a selected temperature-transition point. The desired temperature transition point is specified by a single non-precision resistor coupled in series with the power terminal of the detector. The non-precision resistor and a power supply set a program signal, in the form of a current, into the power terminal of the detector. The programmable temperature detector comprises circuitry for quantizing the program signal into a discrete signal level and for selecting a temperature transition point in response.

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Mountain View, CA, United States of America

Marc E Dagan