B57211P0509M351

Overview

The B57211P0509M351 is a leaded NTC thermistor from the P11 series, designed for inrush current limiting. It features a 13mm diameter disk with UL 94V-0 flame-retardant coating and tinned copper wire leads spaced at 7.5mm. At 25°C, the resistance is 5 Ohms with ±20% tolerance. The maximum steady-state current is 5A, with a stabilized resistance of 0.487 Ohms at maximum current.

Feature Summary

• Leaded thermistor design with kinked tinned copper wire leads
• UL 94V-0 flame-retardant coating on the 13mm disk
• Nickel barrier termination structure for soldering stability

Applications

• Inrush current limiting in power supply circuits
• Circuit protection against voltage spikes
• General electronic equipment overcurrent protection

Procurement Notes

Verify the specific suffix M351 to confirm lead configuration and packaging type. Ensure the application environment does not exceed the maximum steady-state current rating of 5A. Confirm that the 13mm disk size fits the mechanical constraints of the target PCB layout. Check for RoHS compliance status if required by project specifications.

Selection Notes

Select this component when a 5 Ohm initial resistance is required to limit startup current effectively. The 5A steady-state rating suits moderate power applications. Consider the 13mm diameter for thermal dissipation requirements. The leaded format allows for easy manual or wave soldering processes compared to surface mount alternatives.

Part Context

This part belongs to the EPCOS (now TDK) P11 series of NTC inrush current limiters. The series utilizes negative temperature coefficient technology where resistance decreases as temperature rises. This characteristic allows the component to act as a high-resistance barrier during cold start-up and a low-resistance path during normal operation.

Replacement Considerations

BN-LG10Y200MYB from Bourns Inc. is a documented substitute option. Verify electrical parameters such as resistance and current ratings match before substitution.