Patent ID: 8120209
Filing Date: 2012-02-21
Classification: G01R,H02J,Y02T

Abstract:
1. A voltage sensing device comprising: multiple voltage input nodes; a pair of sensing input nodes; a first sensed signal generating part that holds both sensing input nodes of said pair at a reference potential while generating current input to said pair of sensing nodes at values determined by feedback elements, and that generates a pair of first sensed signals according to said generated current; a switch part provided with multiple switches that turn on or off connections between said multiple voltage sensing nodes and said pair of sensing input nodes; input resistors, that have approximately equal resistance values, provided in the current paths between said multiple input nodes and said switch part; a control part that controls said switch part to select a pair of voltage input nodes from said multiple voltage input nodes and connect this selected pair of voltage input nodes and said pair of sensing input nodes in two types of patterns having opposite polarity for each selected pair; and a second sensed signal generating part that generates a second sensed signal according to a difference between said pair of first sensed signals generated by said first sensed signal generating part with said two types of connection patterns, whereby offset in measuring said sensed voltage is reduced or cancelled.