Linear Technology Corporation

Zhizhong Hou

Daniel James Eddleman

Mitchell Edward Lee

James Herr

Christopher Bruce Umminger

Robert Loren Reay

In one embodiment, a pass MOSFET is coupled in series between an input voltage and a load, and a bypass capacitor is connected in parallel with the load. In response to a voltage step across the MOSFET, the MOSFET is adaptively controlled to conduct an in-rush current of 2I=2Iduring the bypass capacitorcharging time, where Iis the capacitive current and Iis the load current. This optimizes the in-rush current to achieve a minimum peak temperature of the MOSFET. In one embodiment, a ramp capacitor connected to the drain of the MOSFET is part of a feedback path that tracks the MOSFET drain voltage to control the gate voltage.

Adaptive in-rush current control for minimizing MOSFET peak temperature upon voltage step

A circuit for protecting a semiconductor element is provided in a system for supplying power from an input node to an output node. The circuit has an analog multiplier responsive to a voltage across the semiconductor element and a current flowing through the semiconductor element to produce an output voltage. A transconductance amplifier is coupled to an output of the analog multiplier for receiving the output voltage of the analog multiplier to produce an output current. An analog RC circuit coupled to the output of the transconductance amplifier is configurable to include a selected number of resistive elements having selected resistance values and a selected number of capacitive elements having selected capacitance values. The configuration of the RC circuit is carried out to provide an RC thermal model that reproduces a desired thermal behavior of the semiconductor element. The RC circuit is responsive to the output current of the transconductance amplifier to produce an output voltage used to control the semiconductor element.

MOSFET protection using resistor-capacitor thermal network

A device having a signal level different from a signal level of an external device includes an interface, such as an IC interface, for providing communications with the external device. The interface is configurable to support communications with the external device either via multiple wires or via a single wire.

Configurable data port for I2C or single-wire broadcast interface

A method of and system for controlling the inrush current generated in a MOSFET of an inrush current control system, wherein the MOSFET includes a source, gate and drain. The dV/dt at the drain of the MOSFET is controlled so as to set the inrush current level as a function of dV/dt, independent of current limit without requiring a separate capacitor connected between the gate and drain of the MOSFET so that the MOSFET can turn on and off more quickly.

Inrush current control system with soft start circuit and method

An output signal is controlled with adjustable hysteresis in response to a variable voltage input signal. One or more signals derived from the input signal are respectively compared with first and second reference voltages of different magnitudes. The output signal changes from a first state to a second state when one of the derived signals reaches a first reference voltage level threshold, and changes from the second state to the first state when a second one of the derived signals reaches a second reference level voltage threshold. A first derived signal may be varied to have a voltage magnitude that is greater or lesser than the voltage magnitude of a second derived signal while maintaining a positive hysteresis level. The circuit may be configured to output a signal representing an undervoltage and/or overvoltage condition of the input signal.

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Fremont, CA, United States of America

Zhizhong Hou