18DA113

Overview

The Vishay Ametherm 18DA113 is a Negative Temperature Coefficient (NTC) ceramic inrush current limiter designed for power supply and motor protection. It features an 18 mm disc diameter with a nominal resistance of 11 kOhms at 25°C and a tolerance of 20%. The component has a B-parameter of 4600 K, indicating its temperature-resistance characteristic curve. It is rated for an energy absorption capability of 100 Joules and operates within a standard industrial temperature range.

Feature Summary

• Provides effective limitation of high inrush currents during power-up sequences to protect sensitive downstream components
• Utilizes NTC ceramic technology to automatically reduce resistance as operating temperature increases during steady-state operation
• Engineered for robust performance in protecting power supplies and electric motors against thermal stress

Applications

• Power supply input stages
• Motor drive circuits
• General electronic equipment requiring surge protection

Procurement Notes

Verify the specific datasheet revision and electrical tolerances directly with the manufacturer or authorized distributors before integration. Confirm that the 11 kOhm resistance and 100 Joule rating align with the target circuit's peak current and energy requirements. Ensure the 18 mm package size fits the available PCB real estate and mounting constraints.

Selection Notes

Select this component when a higher initial resistance is required to limit inrush current in circuits with lower peak power demands compared to larger diameter variants. The 11 kOhm value suggests suitability for low-power signal conditioning or small-signal power inputs where minimal steady-state voltage drop is critical. Evaluate the 4600 K B-parameter against the expected ambient temperature variations to ensure stable resistance characteristics.

Part Context

This part belongs to the Vishay Ametherm family of NTC inrush current limiters, which are widely used for circuit protection. These components serve as passive safety devices that mitigate the stress caused by sudden current surges upon energization, thereby extending the lifespan of connected electronics.

Replacement Considerations

Direct substitutes must match the 11 kOhm resistance, 18 mm diameter, and similar B-parameter. Consider other Vishay Ametherm series parts with identical electrical ratings if availability differs, ensuring the replacement maintains the same physical footprint and thermal performance.