Why are there such electronic components as 0Ω chip resistors?

In our impression, the chip resistor plays a role in blocking the current. But 0 ohm resistance? What can we do with a resistor that can't block the current? In fact, 0Ω resistors do not appear at the beginning, and most of the 0Ω resistors are chip resistors. This is closely related to its use.

When most of the circuit boards are designed with through-hole double-sided boards, there is not much room for 0 ohm resistors. As time goes by, more and more SMD components are used in large-scale industrial production. The same problem is encountered when producing SMD single-sided circuit boards. The flying leads will be difficult to solder to the pads of the SMD. At this time, the use of 0 ohm resistors can "leap" over the thinner circuit and reduce the design. The difficulty.

For the same reason, for patch type circuit boards, it is difficult to use the machine to install the jumper in a unified way. However, the use of empty pads and 0Ω resistors can play the same role as the jumper. Play a certain configuration role.

In fact, in addition to these reasons, the use of 0Ω resistors has additional effects in one way or another. For example, it can be used as a lead for the grounding point, constructing a current loop, and so on. There are also some reasons that are difficult to consider, such as the use of unmarked 0 ohm resistors to act as an anti-copy board in order to facilitate the removal of the measurement. These are all additional usage developments.

Here is a summary of the various uses of 0Ω resistors:

The 0Ω resistor is equivalent to a very narrow current path, which can effectively limit the loop current and suppress noise. Resistance has an attenuation effect in all frequency bands (0 ohm resistance also has impedance), which is stronger than magnetic beads.

It is used for the current loop when crossing the electrical ground plane: when the electrical ground plane is divided, the short return path of the signal is broken. At this time, the signal loop has to be detoured, forming a large loop area, and the influence of the electric field and magnetic field becomes stronger, which is easy Interfering/being disturbed. Connecting a 0Ω resistor across the divided area can provide a shorter return path and reduce interference.

 Configuration circuit: Generally, jumpers and DIP switches should not appear on the product. Sometimes users may change the settings, which may cause misunderstanding. In order to reduce maintenance costs, 0Ω resistors are used instead of jumper wires to be soldered on the board. Vacant jumpers are equivalent to antennas at high frequencies, and the use of patch resistors is effective.