METHOD MEASURING THERMAL RESISTANCE OF TWO-TERMINAL NETWORKS WITH WELL-KNOWN TEMPERATURE COEFFICIENT OF RESISTANCE Russian patent published in 2001 - IPC

FIELD: electronics, inspection of quality of electron articles, evaluation of their temperature margin. SUBSTANCE: method measuring thermal resistance of two-terminal networks with well-known temperature coefficient of resistance consists in transmission through tested two-terminal network of heating current whose value changes by harmonic law with fixed amplitude and period one order higher than thermal constant of time of two-terminal network. Change of voltage drop across two-terminal network is measured on two frequencies: on measurement frequency of heating current and on frequency thrice as much as measurement frequency of heating current. Value of thermal resistance of tested two-terminal network is found by amplitudes of first U_m1 and third U_m3 harmonics of change of voltage by formula Z_t= (1/α•I_m)•[U_a/(U_b-U_a)²], where α is temperature coefficient of resistance; I_m is amplitude of heating current; U_a= 4U_m3, U_b= U_m1+U_m3. EFFECT: raised precision of measurement of thermal resistance of two-terminal networks and reduced expenses. 1 dwg