Teradyne

About: Teradyne is a company organization based out in Boston, Massachusetts, United States. It is known for research contribution in the topics: Signal & Automatic test equipment. The organization has 828 authors who have published 999 publications receiving 15695 citations.

High resolution synthesizer with improved signal purity

Abstract: An automatic test system using a DDS signal generator to create a signal with high spectral purity or a low jitter digital clock. The low jitter clock has variable frequency and is programmed to control other test functions, such as the generation of arbitrary waveforms. The DDS uses a high resolution, high sampling rate DAC to generate a sine wave that is converted to a digital clock. The architecture of the DDS signal generator allows low cost CMOS circuitry to be used to generate the data stream that feeds the high sample rate DAC.

Automatic test equipment with pipelined sequencer

Abstract: Automatic test equipment utilizing a pipelined sequencer to retrieve test vectors from a random access memory during execution of a test pattern. The order of execution of the test vectors need not be sequential and can be dynamically altered by conditions measured during execution of a test pattern. Though pipelined, the sequencer provides one vector per cycle, even if the execution order is dynamically altered. The sequencer, because it is pipelined, can be implemented with relatively low cost, though slower speed, components. The disclosed sequencer is implemented with CMOS components.

Automatic test equipment with narrow output pulses

Abstract: Automatic test equipment suitable for testing high speed semiconductor devices. The test equipment includes a formatter circuit with a flip flop that produces an output in the desired format even if the edge signals that control the setting and resetting of the flip flop overlap. The flip flop allows the test system to generate outputs with narrow pulses, and can generate output pulses that are narrower than the controlling edge signals.

Over-voltage test for automatic test equipment

Abstract: Automatic test equipment including a digital test instrument that may test for and respond to over-voltage conditions. Information on over-voltage conditions may be used in detecting or diagnosing fault conditions within a system under test. Over-voltage conditions may be monitored as part of a test to determine the time and the channels on which they occur. A test may fail if an over-voltage condition is detected and the results of the test may indicate when and where the over-voltage condition occurred. Alternatively, indications of over-voltage conditions may be used to alter the test environment. In response to an over-voltage condition, units under test may be disconnected from the test environment to avoid exposing circuitry within those units to voltage levels that may damage or stress components. Alternatively, indications of an over-voltage condition may be used to disconnect from the test environment equipment that may be generating the over-voltage conditions. Over-voltage conditions are detected in a digital test instrument by additional comparators included in the channel electronic circuits of the test instrument.

Digital phase detector

Abstract: A high performance phase detector includes a local digital oscillator for generating a digital reference signal of programmable frequency and phase. The phase detector accumulates a difference in phase between the digital reference signal and a sampled input signal to produce a measure of phase error. The phase detector can be advantageously used in a frequency synthesizer to produce signals with low phase noise and accurate phase control. Synthesizers of this type can further be used to as building blocks in ATE systems and other electronic systems for generating low jitter clocks and waveforms.