Agere Systems Inc.

Che Choi Leung

Edward Belden Harris

Bruce W McNeill

Canzhong He

Daniel Mark Wroge

David Averill Bell

An IO interface circuit for use in a high voltage tolerant application is provided. The IO interface circuit includes a signal pad and at least a first parasitic bipolar transistor having an emitter adapted for connection to a voltage return of the interface circuit, a base adapted to receive a first control signal, and a collector connected directly to the signal pad in an open collector configuration. The interface circuit further includes a MOS control circuit coupled to the parasitic bipolar transistor and being operative to generate the first control signal. The IO interface circuit may further include an active pull-up circuit connected between a voltage supply of the interface circuit and the signal pad.

High voltage tolerant input/output interface circuit

The specification describes matched capacitor pairs that employ interconnect metal in an interdigitated form, and are made with an area efficient configuration. In addition, structural variations between capacitors in the capacitor pair are minimized to provide optimum matching. According to the invention, the capacitor pairs are interdigitated in a manner that ensures that the plates of each pair occupy common area on the substrate. Structural anomalies due to process conditions are compensated in that a given anomaly affects both capacitors in the same way. Two of the capacitor plates, one in each pair, are formed of comb structures, with the fingers of the combs interdigitated. The other plates are formed using one or more plates interleaved between the interdigitated plates.

Interdigitated capacitors

Processor-implemented techniques for verifying ESD device connectivity in an IC include the steps of: receiving an input dataset including layout parameters corresponding to the integrated circuit; identifying ESD devices based at least in part on the input dataset; extracting devices and parasitic elements in at least a portion of the integrated circuit based at least in part on the input dataset; generating a file including connectivity information and dimensional characteristics for extracted devices and parasitic elements associated with at least the identified ESD devices in the integrated circuit; identifying at least one ESD test based on the identified ESD devices and on connectivity to the identified ESD devices; and performing a linear network analysis for each identified ESD test based at least in part on the file.

Growing community of inventors

Bethlehem Township, PA, United States of America

Che Choi Leung