Four-terminal resistor with four resistors and adjustable temperature coefficient of resistance

摘要

Thermally stable four-terminal resistor (current sensor) is characterized by having the capacity to adjust both resistance and temperature coefficient of resistance (TCR), during manufacturing process. The four-terminal resistor includes 3 or 4 elementary resistors R1-R3 forming a closed loop. Resistor R1 is the principal low-ohmic value resistor. The terminals of resistor R1 serve as “Force” terminals of the four-terminal resistor. Resistors R2, R3 form a voltage divider intended to minimize the TCR of the four-terminal resistor and connected in parallel to resistor R1. The terminals of resistor R3 serve as “Sense” terminals of the four-terminal resistor. Resistor R2 may be split into two resistors: R2a, R2b to simplify the implementation of four-terminal resistor. Elementary resistors R1, R2 must have the same sign of TCR. Target resistance and TCR minimization in four-terminal resistor are reached by adjustment of resistance of the elementary resistors.