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.

A comparison of perturbation theory and the small-slope approximation for acoustic scattering from a rough interface for a Biot medium

Abstract: In this paper, the lowest order small-slope approximation (SSA) scattering cross section for Biot theory is derived. Numerical results are obtained for both backscattering and bistatic scattering using a modified power law spectrum, and these results are compared with those of lowest order perturbation theory (PT). Frequencies ranging from 100 Hz to 3 kHz are used for surfaces with RMS heights h of 0.1 and 1 m and a correlation length l of 10 m. The angle of incidence for the bistatic results is limited to 45/spl deg/. It is found that for the smaller surface height roughness (h = 0.1 m), the SSA and PT give the same results for frequencies up to almost 1 kHz for both backscattering and bistatic scattering. For h = 1 m, the SSA and PT backscatter results are in good agreement at all frequencies for incident grazing angles up to approximately 45/spl deg/. For the bistatic results, the SSA and PT results agree only at low grazing angles of scatter. In the specular region, the results differ significantly.

Technique for programming clocks in automatic test system

Abstract: A system and method for configuring an automatic test system to produce a plurality of clocks from a reference clock includes a user interface and software. The user interface receives a plurality of inputs that specify desired frequencies of the plurality of clocks. In response to a command from the user interface, the software calculates values for dividers coupled to the reference clock, for deriving each of the desired frequencies from the reference clock. According to one embodiment, the desired frequencies form ratios that must be met to satisfy coherence. In calculating the divider values, the software minimizes frequency errors while precisely preserving the required ratios.

Connector-to-pad printed circuit board translator and method of fabrication

Abstract: In one embodiment, a laminated printed circuit board translator is provided. In some embodiments, the translator includes a receiving board adapted to receive a pin, the receiving board includes a plated via extending through the receiving board and has a hole for receiving a pin. An interface board laminated with the receiving board has a controlled depth via extending through it to contact a conductive trace. The conductive trace extends between the receiving board and the interface board to connect the plated via of the receiving board with the controlled depth via of the interface board. The controlled depth via is configured so that it is capable of being plated through a single sided drilled opening in the interface board. Some embodiments have a pad on the interface board connected to the controlled depth via.

Low-spur low-distortion digital-to-analog converter

Abstract: A system and method include receiving an input signal; transmitting high-frequency components of the input signal to a first converter; attenuating low-frequency components of the input signal to a predetermined level such that the low-frequency components of the input signal can be used to correct non-linearity errors introduced by the first converter; transmitting the low-frequency components of the input signal to a second converter; attenuating the high-frequency components of the input signal to a predetermined level such that the high-frequency components of the input signal and dither can be used to correct non-linearity errors introduced by the second converter; converting the high-frequency components to form a first converted signal; converting the low-frequency components to form a second converted signal; and combining the first and second converted signals to form the output signal.

Backplane with routing to reduce layer count

Abstract: An electronic system having a backplane designed for efficient routing of signal traces. The system includes two or more daughter cards that are connected to multiple other daughter cards in the system. These daughter cards are mounted centrally to the backplane in the system. Connections between those two daughter cards and the backplane are made through electrical connectors that are distributed in columns along the length of the daughter cards. The connectors are positioned with space between the connectors. The space forms routing channels such that signals that must be connected to the central cards from a daughter cards on either side may be routed through the routing channels.