Abstract: A method for establishing a test mode in an electronic module (10) having an internal fault detector (26) that limits the current in an output transistor (Q1) when an abnormal signal level appears at an output pin (16). An abnormal signal level is intentionally established on the output pin to enable the fault detector, and such enablement is sensed to trigger the test mode within the module. Apparatus for implementing this method in a voltage regulator is also disclosed.

Abstract: Field Effect Transistors are used to replace mechanical relays and to minimize the distance a Device Under Test (DUT) must drive a signal path to the receiver, to minimize insertion losses in critical paths to the DUT, and generally increase reliability in integrated test systems by eliminating the need for relays to test integrated circuits.

Abstract: Thorough delay testing of a combinational logic circuit is accomplished by changing only one input at a time (a single transition), and checking the output at a predetermined short time later, and arrangements are disclosed for systematically applying to the inputs of a combinational logic circuit all possible single transitions of the binary input signals. One economical test circuit uses a conventional binary counter and an associated ring counter to generate the test signals, in addition to input switching circuits or multiplexers for steering data to the logic to be tested and control circuitry to control the test process.

Abstract: A time-of-use watt-hour meter is provided with demand profile capability that defines a plurality of survey periods and demand intervals. During each survey period, electrical consumption is measured during a plurality of demand intervals. The highest measured interval demand occurring during each survey period is saved and compared to the highest interval demands for subsequent survey periods. The five highest interval demands occurring during a billing period are saved for inspection by both the electric utility and the consumer. The use of the survey periods and demand intervals has the beneficial affect of avoiding clusters of peak periods occurring during a single sustained period of high electrical consumption. The results of the demand profile data compilation can be viewed at the watt-hour meter or remotely.

Abstract: A two level test device for testing printed circuit boards is disclosed, including a housing defining an open chamber and a support platform displaceably connected with the housing for closing the chamber and for supporting the circuit board to be tested. A vacuum device is connected with the housing for creating a negative pressure within the chamber to displace the platform from a first rest position to second and third test positions. In the platform second position, the circuit board contacts the terminal of a test pin for functional testing of the board and in the platform third position, the circuit board contacts the terminals of a pair of test pins for in-circuit testing of the circuit board. The test device is characterized by a stop plate for arresting displacement of the platform in its second and third positions. The stop plate includes a plurality of projections and the housing bottom wall contains a plurality of recesses corresponding with the projections.