MMFR Series Leaded Precision Metal Film Resistor

RESI's MMFR series of precision molded metal film resistors are known for their high stability, tight tolerance, and low temperature coefficient of resistance (TCR). This combination allows them to perform well in various working conditions. These resistors are pre-aged to enhance their long-term stability further, with the test result of 1,000 h down to ±0.05%.

Production of MMFR resistors is strictly controlled and follows an extensive set of instructions established in the production procedure for reproducibility. A homogeneous film of metal alloy is deposited on the surface of ceramic cores (96% AL2O3) and conditioned to achieve the desired stability and temperature coefficients.

A professional laser is pressed on the metalized rods to achieve the target value and perfect electronic performance by smoothly cutting a helical groove in the resistance layer on the ceramic rods without damaging the ceramics. The resistance layers are covered by a protective coating and hard Bakelite designed for electrical, mechanical, and climatic protection.

The TCR of the MMFR series resistors is ±5 ppm/°C, and the tightest tolerance is ±0.05%. This is crucial for applications requiring accurate measurement and control, such as high-precision instruments, experimental equipment, and sensors. MMFR resistors feature an extremely low TCR in a range of -50°C to +125°C.