Heat Resistance/Moisture Resistance Thin Film Resistors

Heat Resistance/Moisture Resistance Thin Film Resistors

Thin film resistors have excellent characteristics such as high precision or low current noise whereas they have problem of being used under high temperature and high humidity. RN73H, with the improved heat resistance and moisture resistance than conventional thin film resistors RN73, can be used under severe environment like automotive purposes.


Heat Resistance

Applying excellent heat resistance material to resistive body, all the type of RN73H except a certain size, achieve higher rated power than RN73. By extending the rated ambient temperature and max. operating temperature(the upper limit of operating temperature range)on the derating curve, the products can be used with higher applicable power at high temperature.

Calculation example of applicable power at ambient temperature 100°C
RN73 1J   Rated Power: 0.063W×0.455(45.5%)=0.029W
RN73H 1J  Rated Power: 0.1W×0.786(78.6%)=0.079W(2.72 times compared to RN73)


Moisture Resistance 

Electric corrosion may be occured in thin film resistors when they are used under high moisture enviroment. RN73H with special protective coating, improved the moisture resistance compared to conventional products and electric corrosion or disconnection are unlikely to be happened. This product shows the excellent characteristics compared to the conventional type in moisture resistance load life test of severe automotive test conditions. 


Comparison of moisture resistance load life test


Test MethodLimit
RN7340°C±2°C、90% to 95%RH、
1000hrs(1.5hrs ON/0.5 hrs OFF)
±0.5%+0.05Ω
RN73H85°C±2°C、85%±5%RH, 
1000hrs(1.5hrs ON/0.5 hrs OFF)
±0.1%+0.05Ω




post time:2018-04-23