About Zero-Ohm Resistor Power Rating

[Kevin_6462]

Inquiries concerning the maximum power rating of a zero-ohm resistor is one of the more frequent questions we receive from customers.

There are two parameters, not normally listed on the datasheet, often used to calculate resistor power handling. One is the tolerance specification. Zero-ohm resistors do not have a tolerance specification. That figure is normally called out as plus-or-minus some percentage of the nominal value of the resistor, which is meaningless at zero ohms.

The second parameter is the maximum power rating, which seems unnecessary as their dissipation is defined by I²R and R here is 0 ohms. However, a zero-ohm resistor is not perfect. Some manufacturers do specify a maximum actual resistance at a rated current, so the rated power can be calculated with the equation I²R. As an example, RK73Z2HTTE from KOA Speer specifies in its datasheet that there is a 50mohm maximum resistance under the condition of maximum continuous current 2A, so its rated power can be obtained.

See also

Resistors

Introduction Resistors, like inductors and capacitors, are passive electronic components which are quite simple in theory but rather more complex when the behaviors of real-world devices are considered. Any resistor that one can build or buy is non-ideal in some respect that renders it unsuitable for some purposes; the various products available offer different balances of imperfection in an effort to be found good enough for others. The goal of this resource is to aid the reader in making inf…

How to Determine Wattage

There are a few methods to quickly determine wattage on a part that doesn’t really list the parameter in the product attributes or the data sheet. Many parts have this rating because they absolutely need it in the description due to it being critical to their design. A few examples include power supplies, resistors, most AC or DC fans, most AC or DC motors, and anything else that deals with power directly. However, there are many electronics parts out there without the rating and this may cause …