It includes the world's fastest semiconductors, lasers able to etch minuscule chip circuits and ultrasecure broadband communications systems.

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Exar, a semiconductor company, designs, develops and markets analog and mixed-signal integrated circuits for use in communications, video and imaging products.

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The closing of borders would deny access to many items made abroad that are needed during a pandemic, including masks and gloves, electrical circuits for ventilators and communications gear and certain pharmaceuticals and their precursors.

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The roughest spot is in communications-infrastructure chipmakers, companies like Vitesse Semiconductor , Applied Micro Circuits , PMC Sierra .

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Its products include integrated circuits that are used in disk drives, solid state drives, high-speed communications systems, computer servers, storage systems, and personal computers.

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