Patent ID: 6433514
Filing Date: 2002-08-13
Classification: H01M,H02J,Y02E

Abstract:
A moisture detection circuit, comprising:a substrate having a reference conductor and a sense conductor formed thereon, the conductors being closely spaced apart such that exposure of the substrate to moisture causes formation of a conductive path carrying a sense current between the conductors when the voltage between the conductors is on the order of a circuit operating voltage; a voltage source coupled between the reference conductor and a reference circuit node to provide substantially the circuit operating voltage therebetween; a current source coupled between the sense conductor and the reference circuit node, the current source generating a bias current sufficient to maintain a first voltage on the sense conductor in the absence of the sense current and to permit the sense conductor to be driven to a second voltage in the presence of the sense current; and a voltage detection component coupled to the sense conductor, the voltage detection component being operative to discriminate between the first and second voltages so as to generate a binary output signal indicating whether the substrate is exposed to moisture.