US 4,053,844 A · Card-reader integrated circuit tester

Abstract

A method and apparatus are described for testing electronic circuit devices for proper operation and parameter tolerance levels. The apparatus includes a card reader for extracting from a plurality of programming cards comparison values against which actual parameter values of a device under test are to be compared; a memory for storing a plurality of comparison values for each parameter of the device to be checked, which different comparison values represent different tolerance levels or bins for the device; test circuitry for measuring the actual values of the parameters of a device under test; a comparator for comparing each of such actual values with the various tolerance comparison values for the same; and a visual display screen for displaying the results of the comparison. The method includes marking a decimal numeric Hollerith code on the programming cards with the comparison values and then feeding the same through a card reader to the memory for later recall of such comparison values as needed for comparisons.

Claims20

Dependent claims

Apparatus for checking one or more electrical parameters of a plurality of similar electronic circuit devices to be tested comprising:

means for extracting from programming means information providing a plurality of differing tolerance comparison values for a parameter of such devices to be checked, said values represent differing classfication groups into which said plurality of similar electronic circuit devices are to be distributed;
means for measuring the value of the parameter of one of said electronic circuit devices to be checked;
means for comparing the measured value of the parameter with said plurality of differing tolerance comparison values to identify a classification group corresponding to said measured value;
and means for displaying the results of said comparison.

1 more element

A test circuit for measuring the input currents flowing into the inverting and non-inverting input terminals of an operational amplifier to be tested comprising:

a pair of second operational amplifiers selected to have input currents at their respective inverting and non-inverting input terminals at least an order of magnitude less than the input currents expected of the operational amplifier to be tested, one of the inverting and non-inverting input terminals of both of said second operational amplifiers being connected to a reference voltage source and the other of said input terminals of each of said second operational amplifiers being connected respectively to an associated one of the inverting and non-inverting terminals of the operational amplifier to be tested;
and a feedback loop on each of said second operational amplifiers extending through a resistance between the output terminal thereof and the one of said inverting and non-inverting input terminals thereof connected to said input terminal of said operational amplifier to be tested, whereby the voltage at the output terminal of each of said second operational amplifiers is proportional to the input current to be measured thereby.

A method for checking one or more electrical parameters of an electronic circuit device comprising the steps of:

providing a programming card having first and second response areas thereon, said first response area being adapted for receipt of indicia indicative of a tolerance comparison value for a parameter of an electronic circuit device to be checked and said second response area being adapted for receipt of indicia indicative of a select classification group represented by any comparison value entered in said first response area;
marking said first response area with indicia indicative of a selected tolerance comparison value for a parameter to be checked;
marking said second response area with indicia indicative of a selected classification group represented by the selected tolerance comparison value;
feeding the marked programming card into a card reader adapted to extract therefrom the information providing said tolerance comparison value and said selected classification group;
measuring the actual value of the parameter to be checked of the electronic circuit device;
comparing the measured value of the parameter with said comparison value therefor;
and displaying the results of said comparison.

4 more elements

Dependencies are inferred from the claim text.

Card-reader integrated circuit tester

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Card-reader integrated circuit tester

Life of this patent

Abstract

Claims20