DEVICE FOR MEASURING TRANSITION-BODY HEAT RESISTANCE OF DIGITAL INTEGRAL MICROCIRCUITS Russian patent published in 2001 - IPC

FIELD: electronic engineering. SUBSTANCE: operation principles involve defining linear law of changing heating power with corresponding pulse-switching frequency modulation and measuring the rate of parameter temperature sensitivity changes. The device has contact box with terminals for connecting leads of a digital integral circuit under control. Power supply source is connected to the terminals for connecting leads of microcircuit power supply. Pulse-switching oscillator output having linearly increasing succession frequency is connected to terminals for connecting leads of outputs being inputs to several (K) microcircuit gates. K <n, where n is the total number of logical circuit gates. One output of reference voltage source is connected to an input of the first comparator unit. The second output is connected to an input of the second comparator unit, respectively. The other inputs of both units are connected to the terminal for connecting output of that logical circuit gate, which state does not change. Outputs of both comparator units are connected to control unit. Its output is connected to one of inputs of temporary selector unit, the second output being connected to pulse-switching oscillator. Temporary selector unit output is connected to counting input of reversed counter which control input is connected to the second control unit output. Reversed counter outputs are connected to indicator unit inputs. EFFECT: enhanced accuracy of measurements. 2 dwg