SG339

Inrush Current Limiters (ICL) Overview

The SG339 is a SURGE-GARD series NTC thermistor inrush current limiter manufactured by Vishay / Ametherm. Designed for PCB mount applications, it features radial kinked leads with a lead spacing of 0.35 inches and a lead diameter of 0.04 inches. The component has a resistance of 12 Ohms with a tolerance of 10%, rated for a continuous current of 4 A and a voltage of 265 VAC. It operates within a temperature range of 0°C to +65°C. Physical dimensions include a diameter of 0.5 inches (12.70 mm), width of 0.35 inches, and height of 0.25 inches.

Inrush Current Limiters (ICL) Feature Summary

• Utilizes negative temperature coefficient (NTC) technology to limit initial surge currents during power-up
• Features radial kinked lead configuration for secure through-hole PCB mounting
• Designed for high reliability in AC line voltage environments up to 265 VAC

Inrush Current Limiters (ICL) Applications

• Power supply input stages
• Electronic equipment protection circuits
• AC mains filtering applications

Inrush Current Limiters (ICL) Procurement Notes

Verify the specific lead configuration matches the design requirements, as this model utilizes kinked leads rather than straight leads. Confirm that the 12 Ohm cold resistance and 4 Ampere rating are sufficient for the target circuit's peak inrush current. Ensure the operating temperature range of 0°C to +65°C aligns with the environmental conditions of the final assembly. Check RoHS compliance status if required by project specifications.

Inrush Current Limiters (ICL) Selection Notes

Select this component when a moderate inrush current limiting value is required for low-to-medium power AC applications. The 12 Ohm resistance provides a balance between surge suppression and steady-state power dissipation. Consider the physical footprint constraints, as the 0.5-inch diameter requires adequate board space. This model is suitable for designs where standard radial mounting is preferred over surface mount alternatives.

Inrush Current Limiters (ICL) Part Context

The SG339 belongs to the SURGE-GARD family of inrush current limiters produced by Vishay / Ametherm. This series specializes in NTC thermistors designed to protect sensitive electronic components from damaging current spikes. The SG339 specifically targets applications requiring robust protection for AC-powered devices, offering a standardized solution for common power supply inputs.

Inrush Current Limiters (ICL) FAQ

What is the lead configuration for the SG339?

The SG339 features radial kinked leads, which are bent at a right angle to facilitate secure insertion into printed circuit boards.

Is the SG339 suitable for DC applications?

The datasheet specifies a voltage rating of 265 VAC. While NTC thermistors can function in DC circuits, official documentation primarily certifies this model for AC line voltage applications.