Patent ID: 7312653

Claim:
A reverse polarity protected system for a voltage source that includes positive and negative terminals, comprising: a polarity-sensitive device that has a first terminal that communicates with the positive terminal of the voltage source, and that includes a second terminal; a low-resistance switch that has a first terminal that communicates with the positive terminal of the voltage source, a second terminal that communicates with the negative terminal of the voltage source, and a third terminal that communicates with said second terminal of said polarity-sensitive device, wherein said low-resistance switch assumes a conducting state between its second and third terminals when a first voltage at the positive terminal of the voltage source minus a second voltage at the negative terminal of the voltage source is greater than a first threshold voltage, and wherein said low-resistance switch assumes a non-conducting state between its second and third terminals when said first voltage minus said second voltage is less than a second threshold voltage; and a drive circuit having first and second terminals, wherein said first terminal of said drive circuit communicates with a control terminal of said polarity-sensitive device, and said second terminal of said drive circuit communicates with said second terminal of said polarity-sensitive device.