MF-R300-2-14-99

Overview

The MF-R300-2-14-99 is a polymeric positive temperature coefficient (PPTC) resettable fuse manufactured by Bourns Inc. This component belongs to the MF-R series and is designed for circuit protection against overcurrent conditions. It features a radial leaded package suitable for through-hole PCB mounting. The device operates with a maximum voltage of 30 VDC and maintains a hold current of 3 A. It trips at a current of 6 A and can withstand a maximum trip current of 40 A. The initial resistance is typically 50 mOhms, with an operating temperature range from -40°C to +85°C.

Feature Summary

• Provides automatic circuit protection by increasing resistance in response to overcurrent or overheating events.
• Offers resettable functionality, allowing the component to return to low-resistance state after fault clearance and cooling.
• Utilizes a radial disc package design for reliable through-hole integration on printed circuit boards.

Applications

• Overcurrent protection in consumer electronics circuits
• Protection of battery packs and power supply lines
• Surge protection in communication equipment interfaces

Procurement Notes

Verify the specific suffix -2-14-99 corresponds to the tape and reel packaging variant rather than bulk packaging when sourcing. Confirm that the 30V 3A rating aligns with the target circuit's voltage and continuous current requirements. Ensure the radial lead spacing matches the PCB footprint design. Check for RoHS compliance documentation if required by project specifications.

Selection Notes

Select this component when a resettable fuse is preferred over traditional fuses to reduce maintenance costs. The 3A hold current and 30V max voltage define the operational limits. Consider the trip time characteristics and maximum trip current of 40A for fault handling capability. Evaluate the thermal environment to ensure operation within the -40°C to +85°C range without derating issues.

Part Context

This part is part of Bourns' Multifuse MF-R series, which focuses on high-reliability PPTC devices. The series offers various current ratings and package options. The MF-R300 specifically targets applications requiring moderate current protection with resettable convenience. It complements other Bourns circuit protection products like varistors and standard fuses.

Replacement Considerations

Direct substitutes include other MF-R series variants with matching electrical ratings. Cross-reference with similar radial PPTC fuses from other manufacturers ensuring identical hold current, trip current, and voltage ratings. Verify package dimensions and lead spacing compatibility before substitution.

FAQ

What is the difference between hold current and trip current for this device?

Hold current (3A) is the maximum current the device can carry indefinitely without tripping. Trip current (6A) is the minimum current at which the device will switch to a high-resistance state within a specified time.

Is the MF-R300-2-14-99 polarized?

No, PPTC resettable fuses are non-polarized components and can be installed in either direction on the PCB.