Raytheon Company

Thomas H Alford

Michael S Lackey

Robert F Stiffler

David M Filgas

A multi-stage laser drive circuit includes a variable common potential source, a PA light-emitting array between a storage capacitor and a current node, first and second low-side linear current sinks in electrical communication with the current node, and a second master oscillator (MO) light-emitting array in electrical communication between the current node and the first low side linear current sink. A trickle current circuit drives a low-value trickle current through the arrays, and a sense circuit senses the trickle current. Also, the headroom voltage across a pass element in the first low-side linear constant current sink is monitored and adjusted for maximum efficiency.

Apparatus and method for driving laser diode arrays with high-power pulsed currents using low-side linear drive with laser diode array protection and power efficiency monitoring and adjustment

Provided are assemblies and processes for activating light emitting devices. A first current sink is in electrical communication with a common source through a current node and configured to draw a first current through the current node in response to a respective control signal. A second current sink is also provided in electrical communication with the current node and in parallel with the first current sink, also configured to draw a second current through the current node in response to a respective control signal. An aggregate current is drawn through the array, determined as a combination of the first and second currents. A commanded current from the first current sink can be shunted around the second array and the second current sink, providing a capability to series both the first and second laser diode light-emitting arrays, while simultaneously drawing different current amplitudes through each array from a common potential source.

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Lomita, CA, United States of America

Thomas H Alford