what is a zero ohm resistor used for
They can be used in a circuit for several reasons: 1  On a multi-layer board, sometimes the board is too tight to route without crossing back and forth several times, and a simple jumper can really make the routing much easier, since it can hop across several traces. 2  On a single-sided board, they can replace wire jumpers. Zero ohm resistors are used where the designer may want to modify the circuit after it is built. It is easier to add or unsolder a surface-mount resistor than it is to bridge traces or cut a trace. During prototyping, a designer might include two versions of a circuit, and then use jumpers (zero ohm resistors) to enable one or other other.