Reverse Polarity Switches Protect Mobile Devices

A line of low-power, application-specific, reverse polarity protection switches from Fairchild Semiconductor provide low resistance and fast response, with nearly 50x less power consumption than a traditional series Schottky solution at 1 A. The company's initial offerings in this family of switches are the FR011L5J low-side reverse polarity protector and the FR014H5JZ high-side reverse polarity protector with integrated over-voltage transient suppression. Both protectors dissipate less than 0.02 W during 1 A normal operation, and less than 20 µW in a 16 V reverse bias event, a performance not possible with a diode solution. The low dissipation minimizes the need for heat sinking and allows for smaller package sizes and reduced board space requirements. Additionally, the devices’ nSec scale reverse bias blocking response time blocks negative transients and other potentially damaging dc events. Both switches are USB tested and compatible. The FR011L5J is priced at $0.35 each/1,000 and the FR014H5JZ is $0.56 each/1,000. Samples are available upon request and delivery is 8-12 weeks ARO.