The 102°C heat rise shown here would indicate there will be additional thermal reduction techniques needed to keep
this part under 105°C total hot spot temperature if this part is to be used at 0.75 watts of power. However, this same
part at the usual power rating for this size would have a heat rise of around 72°C. This additional heat rise may be dealt
with using wider conductor traces, larger solder pads and land patterns under the solder mask, heavier copper in the
conductors, via through PCB, air movement, and heat sinks, among many other techniques. Because of the variety of
methods customers can use to lower the effective heat rise of the circuit, resistor manufacturers simply specify power
ratings with the limitations on ambient air temperature and total hot spot temperatures and leave the details of how to
best accomplish this to the design engineers. Design guidelines for products in various market segments can vary
widely so it would be unnecessarily constraining for a resistor manufacturer to recommend the use of any of these
methods over another.
Note: The final resistance value can be affected by the board layout and assembly process, especially the size of the
mounting pads and the amount of solder used. This is especially notable for resistance values ≤ 50mΩ.
This should be taken into account when designing.
Stackpole Electronics has joined the worldwide effort to reduce the amount of lead in electronic components and to meet the various
regulatory requirements now prevalent, such as the European Union’s directive regarding “Restrictions on Hazardous Substances”
(RoHS 3). As part of this ongoing program, we periodically update this document with the status regarding the availability of our
compliant components. All our standard part numbers are compliant to EU Directive 2011/65/EU of the European Parliament as
amended by Directive (EU) 2015/863/EU as regards the list of restricted substances.
“Conflict Metals” Commitment
We at Stackpole Electronics, Inc. are joined with our industry in opposing the use of metals mined in the “conflict region” of the
eastern Democratic Republic of the Congo (DRC) in our products. Recognizing that the supply chain for metals used in the
electronics industry is very complex, we work closely with our own suppliers to verify to the extent possible that the materials and
products we supply do not contain metals sourced from this conflict region. As such, we are in compliance with the requirements of
Dodd-Frank Act regarding Conflict Minerals.
Compliance to “REACH”
We certify that all passive components supplied by Stackpole Electronics, Inc. are SVHC (Substances of Very High Concern) free
and compliant with the requirements of EU Directive 1907/2006/EC, “The Registration, Evaluation, Authorization and Restriction of
Chemicals”, otherwise referred to as REACH. Contact us for complete list of REACH Substance Candidate List.
It is the policy of Stackpole Electronics, Inc. (SEI) to protect the environment in all localities in which we operate. We continually
strive to improve our effect on the environment. We observe all applicable laws and regulations regarding the protection of our
environment and all requests related to the environment to which we have agreed. We are committed to the prevention of all forms