The Allegro SLA7062 IC's can be purchased from:
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They have plenty in stock for immediate shipment. (707) 448-375Also available is a PC board for the SLA7062M and a kit to build complete unipolar microstepper driver using this IC. The kit ha optoisolated inputs and a idle current reduction feature that reduce the motor current by 50% when the drive has not received step pulse after a 2 second delay
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