The MF72 series 8D-13 is a directly heated, power-type negative temperature coefficient thermistor designed to dynamically suppress startup inrush current in electronic devices. Its rated zero-power resistance is 8Ω ±20%, tested at 1.5VDC at 25°C, and its material constant B value is 2800K ±10%.
During startup, its high-resistance state effectively limits high current surges. After steady-state operation, the resistance self-heats to a residual value of 0.194Ω, providing effective thermal buffering. The product of a thermal time constant of 68 seconds and a dissipation factor of 15mW/°C reaches 1020mJ/°C, providing strong surge protection.
With a maximum steady-state current of 4A, it supports large loads of 330μF in 240V systems or 1200μF in 120V systems. The thickened wafer design features a diameter of 14.5mm, a thickness of 6mm, and a fixed lead spacing of 7.5mm.
With an operating temperature range of -40°C to +200°C, it is optimized for high-power applications and is suitable for industrial-grade UPS, high-power heaters, and power conversion systems. The device utilizes a phenolic resin package and CP wire leads, offering four lead configurations: inward curvature, outward curvature, side curvature, and straight, ensuring mechanical adaptability in extreme environments.