Patent ID: 7203455
Filing Date: 2007-04-10
Classification: G09B

Abstract:
1. An electronic user input device having a platform with a first, generally planar, user contact surface overlying a first, generally planar sensor, the first sensor being formed by separate and separated first and second sets of generally parallel, individual conductive lines transversely crossing over each other beneath the user contact surface of the platform, each pair of crossing lines defining a cross-point, the device characterized by: a radio frequency oscillating signal generator cyclically coupled to individual conductive lines of the first set; a synchronous detection circuit operatively coupled with the generator and with individual conductive lines of the second set to identify user selected individual cross-points of the first and second sets of lines of the array; and a transistor coupling between each conductive line of the second set and the synchronous detection circuit, each individual conductive line of the second set being coupled with a base of the transistor coupled with the synchronous detection circuit.