公开(公告)号：US4378549A

公开(公告)日：1983-03-29

申请号：US185756

申请日：1980-09-10

申请人： Joseph Szware

发明人： Joseph Szware

IPC分类号： H01C7/22 ,  H01C17/07 ,  H01C17/23 ,  H01C10/00

CPC分类号： H01C17/23 ,  H01C17/07 ,  H01C7/22 ,  Y10T29/49099

摘要： Improved resistive electrical components are disclosed comprising an insulating or insulated substrate, a resistive foil bonded to the substrate having photoetched therein a pair of terminal pads for making electrical connections to the component and a system of resistive paths interconnecting the terminal pads, said system including an unadjustable section or sections and a plurality of adjustable sections, each having an adjustment tab associated therewith, said tab being removable to modify said section resistance and thereby altering the total resistance presented by the component between its terminal pads, the configurations of the sections differing from each other in a modified geometric progression so that the total resistance of said component is altered by a differing amount depending on which of the sections is modified by removal of its associated adjustment tab, whereby the total resistance of the component may be systematically varied in a sequence of successive steps to achieve a desired ultimate value of the total resistance of the component to the desired degree of accuracy with the least number of steps, the most effective use of substrate surface area, the least contribution to reliability degradation, and the lowest cost. Adjustment of the total resistance of the component to its desired ultimate value and precision is assisted by monitoring the component resistance while making successive adjustments. Placement of said adjustment tabs along one edge of said substrate simplifies manual adjustment and makes practical the use of automatic apparatus controlled by a monitor.