AS322R025

Overview

The Vishay Ametherm AS322R025 is an NTC thermistor inrush current limiter designed for radial PCB mounting. It features a nominal resistance of 2 Ohms with a tolerance of ±25% and a continuous current rating of 25 A. The component supports voltage ratings up to 680 VAC across various configurations (120, 240, 480, 680 VAC). It has a maximum peak reverse current of 10 μA and withstands 300 Joules of inrush energy. Physical dimensions include a diameter of 37 mm, width of 6.5 mm, lead spacing of 19 mm, and lead diameter of 9.5 mm.

Feature Summary

• Radial through-hole construction for direct printed circuit board installation
• Capable of absorbing high-energy transient surges during power-up cycles
• Provides stable resistance characteristics under varying thermal conditions

Applications

• Power supply input stages requiring surge protection
• Industrial control systems managing high initial load currents
• Motor drive circuits limiting startup current spikes

Procurement Notes

Verify the specific voltage rating configuration required for the target application against the datasheet specifications. Confirm that the physical footprint matches the PCB layout constraints, particularly the lead spacing and body diameter. Ensure the thermal environment allows for adequate heat dissipation given the component's power handling capabilities.

Selection Notes

Select this component when a robust solution for limiting high inrush currents is needed in space-constrained PCB designs. The 2-ohm resistance value offers a balance between effective current limiting and steady-state power loss. Consider the 25-ampere continuous rating to ensure the device can handle the operational load without overheating or degradation over its intended service life.

Part Context

This part belongs to the AS32 series of inrush current limiters manufactured by Vishay Ametherm. These components are specifically engineered as negative temperature coefficient thermistors to protect sensitive electronic equipment from damaging current spikes during initial energization phases.

Replacement Considerations

Public confirmed substitute part numbers: None identified.