Lockheed Martin Corporation

Physio-control Manufacturing Corporation

Medtronic Physio-control Manufacturing Corporation

Physio-control, Inc.

Lawrence A Borschowa

Joseph Leo Sullivan

Richard C Nova

Matthias P Savage-Leuchs

Eric C Honea

Jason D Henrie

Anping Liu

Fred William Chapman

Tarek Z Elabbady

Barry F Waltman

Apparatus and method for generating controlled-linewidth laser-seed-signals for high-powered fiber-laser amplifier systems. In some embodiments, the natural chirp (frequency change of laser light over a short start-up time) of a DBR laser diode when driven by pulsed current is used to broaden the linewidth of the laser output, while adjusting the peak current and/or the pulse duration to obtain the desired linewidth.

Method and apparatus to suppress gain-switched spikes in fiber laser amplifier systems

Apparatus and method to suppress gain-switched spikes in fiber laser amplifier systems

Apparatus and method for driving laser diodes with electrical power in pulsed operation. Pulsed power, for example using pulse-width modulation, is applied through an inductor in one or more parallel regulator circuits having little or no output capacitance to provide a high-efficiency laser-diode-driver power supply. Some embodiments that use two or more parallel regulator circuits in the laser-diode driver, drive each from a different phase of a clock signal. Some embodiments provide a first DC-to-DC converter has a relatively high-voltage input (e.g., about 275 volts, 0.75 amps) and an intermediate output of, e.g., 11 to 15 volts, 15 to 11 amps used to charge a storage capacitor, and a second DC-to-DC converter diode driver having one or more parallel circuits (each having, e.g., a PWM switching-mode controller and its respective switch, inductor, and diode) to turn on, regulate, and turn off a constant laser-diode current through one or more laser diodes.

Method and apparatus for driving laser diodes

Apparatus and method for generating optical-seed pulses for high-powered fiber-laser amplifier systems

Apparatus and method for driving laser diodes

Apparatus and method for temporally shaping drive current to seed-signal-laser-diodes for high-powered fiber-laser amplifier systems

Apparatus and method for generating controlled-linewidth laser-seed-signals for high-powered fiber-laser amplifier systems

An external defibrillator/pacer includes an output circuit with four legs arrayed to form an H-bridge. Each leg of the output circuit contains a switch. In a defibrillation mode, pairs of switches in the H-bridge are selectively switched to generate a biphasic defibrillation pulse. Three switches are silicon controlled rectifiers (SCRs). Gate drive circuits are coupled to the SCRs to bias the SCRs with a voltage that allows the SCRs in response to control signals. One switch includes an insulated gate bipolar transistor (IGBT). A gate drive circuit is coupled to the gate of the IGETs to provide a slow turn-on and a fast turn-off of the IGBT. In a pacing mode, a bypass circuit or current source circuit is used to provide a current path bypassing an SCR switch, which cannot be triggered by the relatively low current of pacing pulses.

Circuit for performing external pacing and biphasic defibrillation

An external defibrillator with an output circuit having four legs arrayed in the form of an 'H' (an 'H-bridge') is disclosed. The output circuit is designed to be able to conduct a range of defibrillation pulse energies, from below 50 joules to above 200 joules. Each leg of the output circuit contains a solid-state switch. By selectively switching on pairs of switches in the H-bridge, a biphasic defibrillation pulse may be applied to a patient. The switches in three of the legs of the H-bridge output circuit are preferably SCR switches, while the fourth leg includes an IGBT switch. In one embodiment, a single power switch is utilized in each of the legs of the H-bridge output circuit, and are included in a single integrated module or package. The use of single semiconductor switches in an integrated surface mountable module or package simplifies the assembly and manufacturing of the defibrillator device. The use of a single IGBT in a leg of the H-bridge (as opposed to two or more IGBTs in series) also greatly simplifies the drive circuitry required to turn on and off the IGBT.

H-bridge circuit for generating a high-energy biphasic waveform in an external defibrillator using single SCR and IGBT switches in an integrated package

An upgrade kit and method for converting a typical monophasic defibrillator into a biphasic defibrillator is provided. The upgrade kit is easily connected to a typical monophasic defibrillator and uses control signals that are commonly available in most monophasic defibrillators. Such control signals include the signals for transferring the defibrillation pulse to the patient, and for dumping unwanted energy from the energy storage capacitor. In addition, the upgrade kit avoids the need for information as to the charge level of the storage capacitor by using a discharge method that allows the production of proper biphasic defibrillation pulses regardless of the initial energy settings of the storage capacitor. More specifically, the upgrade kit determines the desired length of the biphasic defibrillation pulses according to two measurements which are taken during the defibrillation pulse. These two measurements are converted to an index referenced in a look-up table to determine the desired lengths of the two phases of the biphasic defibrillation pulse.

Method and apparatus for converting a monophasic defibrillator to a biphasic defibrillator

An external defibrillator with an output circuit having four legs arrayed in the form of an &ldquo;H&rdquo; (an &ldquo;H-bridge&rdquo;) is disclosed. The output circuit is designed to be able to conduct a range of defibrillation pulse energies, from below 50 joules to above 200 joules. Each leg of the output circuit contains a solid-state switch. By selectively switching on pairs of switches in the H-bridge, a biphasic defibrillation pulse may be applied to a patient. The switches in three of the legs of the H-bridge output circuit are preferably silicon controlled rectifiers (SCRs). Gate drive circuits are coupled to the SCRs to bias the SCRs with a voltage that allows the SCRs to remain turned-on even when conducting low current. The switch in the fourth leg is preferably a pair of insulated gate bipolar transistors (IGBTs) coupled in series. A gate drive circuit is coupled to the gate of the IGBTs to provide a slow turn-on and a fast turn-off of the IGBTs. The gate drive circuit also biases the IGBTs with a sufficient voltage to allow the IGBTs to withstand a shorted discharge of the external defibrillator through the output circuit. The circuit also includes a protective component that has both inductive and resistive properties. An internal energy dump may be performed by biasing on two legs on the same side of the H-bridge output circuit, thus eliminating the need for a separate energy dump circuit. Methods for testing the H-bridge and verifying its integrity are also disclosed.

H-bridge circuit for generating a high-energy biphasic waveform in an external defibrillator

A solid-state defibrillation circuit for applying a multiphasic defibrillation pulse to a patient is disclosed. The circuit eliminates the need for a mechanical relay, and provides for a current limiting circuit for limiting leakage currents that would otherwise flow to the patient from the solid-state components, and for preventing the short-circuiting of a defibrillation pulse from a second defibrillator. In one embodiment, the output circuit of the defibrillator comprises an H-bridge, and the current limiting circuit comprises a plurality of resistors coupled in parallel with each of the legs of the H-bridge. The plurality of resistors allow current flow which reduces the voltage potential across the patient that is caused by the leakage currents through the output circuit. The current limiting circuit also includes a shunt resistor for shunting leakage currents away from the patient. The current limiting circuit also includes a non-linear element, such as an MOV or tranzorb in series with the output of the defibrillation circuit for limiting the leakage currents. The current limiting circuit also includes a diode coupled in series with one of the solid-state switches of the output circuit, for helping prevent voltage breakdown across the switches of the output circuit when an external energy shock is applied from an outside source, such as from a second defibrillator.

Solid-state multiphasic defibrillation circuit

An external defibrillator/pacer (,) includes an output circuit (,) with four legs arrayed to form an H-bridge coupled to an energy storage capacitor. The energy storage capacitor delivers an external defibrillation pulse with stored energy during a defibrillation mode and an external pacing pulse during a pacing mode. Each leg of the output circuit contains a switch (SW,-SW,). In a defibrillation mode, pairs of switches in the H-bridge are selectively switched to generate a biphasic defibrillation pulse. Three switches (SW,, SW,, SW,) are silicon controlled rectifiers (SCRs). Gate drive circuits (,) are coupled to the SCRs to bias the SCRs with a voltage that allows the SCRs in response to control signals. One switch (SW,) includes an insulated gate bipolar transistor (IGBT). A gate drive circuit (,) is coupled to the gate of the IGBTs to provide a slow turn-on and a fast turn-off of the IGBT. In a pacing mode, a bypass circuit or current source circuit is used to provide a current path bypassing an SCR switch (SW,), which cannot be triggered by the relatively low current of pacing pulses. One of the SCRs (SW,) may be replaced with an IGBT to allow generation of the pacing pulse with opposite polarity of the first phase of the defibrillation pulse.

An external defibrillator with an output circuit having four legs arrayed in the form of an &ldquo;H&rdquo; (an &ldquo;H-bridge&rdquo;) is disclosed. The output circuit is designed to be able to conduct a range of defibrillation pulse energies, from below 50 joules to above 200 joules. Each leg of the output circuit contains a solid-state switch. By selectively switching on pairs of switches in the H-bridge, a biphasic defibrillation pulse may be applied to a patient. The switches in three of the legs of the H-bridge output circuit are preferably silicon controlled rectifiers (SCRs). Gate drive circuits are coupled to the SCRs to bias the SCRs with a voltage that allows the SCRs to remain turned-on even when conducting low current. The switch in the fourth leg is preferably a pair of insulated gate bipolar transistors (IGBTs) coupled in series. A gate drive circuit is coupled to the gate of the IGBTs to provide a slow turn-on and a fast turn-off of the IGBTs. The gate drive circuit also biases the IGBTs with a sufficient voltage to allow the IGBTs to withstand a shorted discharge of the external defibrillator through the output circuit. The circuit also includes a protective component that has both inductive and resistive properties. An internal energy dump may be performed by biasing on two legs on the same side of the H-bridge output circuit, thus eliminating the need for a separate energy dump circuit.

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Woodinville, WA, United States of America

Lawrence A Borschowa