Hewlett-packard Company

Wayne R Chism

Philip N King

Larry G Smeins

An automated apparatus and method for in-circuit testing of a coder/decoder circuit mounted a telecommunications card. The automated apparatus is capable of testing the functioning of the coder/decoder circuit: by applying at least one analog voltage signal to the transmit pin and recording the resulting digital serial output signals and by applying at least one pattern of digital signals to the digital serial input pin and recording the resulting analog signals on the receive pin. In conducting these tests, the automated apparatus electrically overdrives any analog or digital signal from associated components on the circuitry.

Apparatus for the automatic in-circuit testing of coder/decoder

A method and apparatus for providing pulse signals from a driver circuit in an in-circuit overdrive/functional tester to a probe, which tester provides a control signal representative of a command for the driver circuit to provide logic signals, includes adjusting the transition time of the logic signals so that the transition time is equal to twice the time it takes the pulse signal to travel from the driver circuit to the end of the probe and back. The method or apparatus for adjusting the rise time of the control signal can include adjusting the slew rate of the control signal. Pulse signals produced by such a method or apparatus have clean edges, have slew rates which are twice as fast as the slew rates of the driver signals and have zero propagation delay when measured at the fifty percent point.

Driver circuit for providing pulses having clean edges

A device and process for programmatically controlled in-circuit pin checks and gross functionality tests of analog to digital converters. The tests provide deterministic bit checks for higher order bits and non-deterministic bit checks of lower order bits independent of other circuitry on the printed circuit board of which the digital to analog converter is a component.

Programmatically generated in-circuit test of analog to digital

A device and process for programmatically controlled in-circuit pin checks and gross functionality tests of digital to analog converters. The tests provide deterministic bit checks for higher order bits and non-deterministic or 'delta' bit checks of low order bits independent of other circuitry on the printed circuit board of which the digital to analog converter is a component.

Programmatically generated in-circuit test of digital to analog

An automated apparatus and method for in-circuit testing of a subscriber line interface circuit mounted on a telecommunications card. The automated apparatus is capable of testing the functioning of the subscriber line interface circuit: by applying analog voltage to the tip and ring pins and recording the resulting transmit signals, by applying at least one analog voltage signal to the receive pin and recording the resulting signals on the tip and ring pins, by applying onhook and offhock signals to the tip and ring pins and receiving the resulting hook status signal, and by applying a ring command to the ring control pin and recording the resulting ring signal and then applying an offhook signal to the tip and ring pins and receiving the resulting ring trip signal. In conducting these tests, the automated apparatus electrically overdrives any analog or digital signal from associated components on the circuitry.

Apparatus for the automatic in-circuit testing of subscriber line

A device and process for programmatically generated and controlled in-circuit pin tests and gross functionality tests of operational amplifiers. The tests provide basic functionality verification of amplifier functions independent of other circuitry on the printed circuit board of which the operational amplifier is a component.

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Greeley, CO, United States of America

Wayne R Chism