摘要 |
A device (110) includes a sensing element (26) having drive nodes (34, 36) and sense nodes (42, 44). Parasitic capacitance (22) is present between drive node (34) and sense node (42). Likewise, parasitic capacitance (24) is present between drive node (36) and sense node (44). When a drive signal (56) is applied between drive nodes (34, 36), a parasitic current (70) between drive and sense nodes (34, 42) and a parasitic current (72) between drive and sense nodes (36,44) is created due to the parasitic capacitances (22, 24). A capacitive network (112) is coupled between the drive node (36) and the sense node (42) to create a correction current (134) through capacitive network (112) that cancels parasitic current (70). Likewise, a capacitive network (114) is coupled between the drive node (34) and the sense node (44) to create a correction current (138) through capacitive network (112) that cancels parasitic current (72). |