Current Noise of Resin Type and Cermet Type Thick Film Resistors

Abstract

The current noise indices (C.N.I.) depend linearly on the logarithmic values of sheet resistivity(log⁡ ρS), in both carbon black/resin and thallium oxide/glass resistors, and can be expressed asC.N.I. = A + B log⁡ ρS. The geometrical dependency on C.N.I. in both types of resistor can be expressed asC.N.I. = A′ − B′ log⁡ (L, W, T), whereA,B,A′ andB′ are constants. The dependency of noise e.m.f. (νn) on the applied dc voltage (V), i.e., the values ofαinνn2¯∝Vα, can be obtained from the slope of C.N.I. versuslog⁡ (L)lines, associated with a model based on the noise generator approximation.