3312 - 2 mm SMD Trimming Potentiometer

Application Notice

MFAN 12/18

Specifications are subject to change without notice.

Users should verify actual device performance in their specific applications.

The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.

Bourns® Multifuse® PPTC Resettable Fuses

• Users are responsible for independent and adequate evaluation of Bourns® Multifuse® Polymer PTC devices in the user’s

application, including the PPTC device characteristics stated in the applicable data sheet.

• Polymer PTC devices must not be allowed to operate beyond their stated maximum ratings. Operation in excess of such

maximum ratings could result in damage to the PTC device and possibly lead to electrical arcing and/or fire. Circuits with

inductance may generate a voltage above the rated voltage of the polymer PTC device and should be thoroughly evaluated

within the user’s application during the PTC selection and qualification process.

• Polymer PTC devices are intended to protect against adverse effects of temporary overcurrent or overtemperature

conditions up to rated limits and are not intended to serve as protective devices where overcurrent or overvoltage conditions

are expected to be repetitive or prolonged.

• In normal operation, polymer PTC devices experience thermal expansion under fault conditions. Thus, a polymer PTC

device must be protected against mechanical stress, and must be given adequate clearance within the user’s application to

accommodate such thermal expansion. Rigid potting materials or fixed housings or coverings that do not provide adequate

clearance should be thoroughly examined and tested by the user, as they may result in the malfunction of polymer PTC

devices if the thermal expansion is inhibited.

• Exposure to lubricants, silicon-based oils, solvents, gels, electrolytes, acids, and other related or similar materials may

adversely affect the performance of polymer PTC devices.

• Aggressive solvents may adversely affect the performance of polymer PTC devices. Conformal coating, encapsulating,

potting, molding, and sealing materials may contain aggressive solvents including but not limited to xylene and toluene,

which are known to cause adverse effects on the performance of polymer PTCs. Such aggressive solvents must be

thoroughly cured or baked to ensure their complete removal from polymer PTCs to minimize the possible adverse effect

on the device.

• Recommended storage conditions should be followed at all times. Such conditions can be found on the applicable data

sheet and on the Multifuse® Polymer PTC Moisture/Reflow Sensitivity Classification (MSL) note:

https://www.bourns.com/docs/RoHS-MSL/msl_mf.pdf