The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 16, 1994
Filed:
Feb. 24, 1993
David Thomson, Fremont, CA (US);
Analog Devices, Inc., Norwood, MA (US);
Abstract
A voltage attenuation network includes one or more cascaded resistor ladder stages, with decremented voltage taps provided at successive cascaded steps within each stage. Each stage includes a termination step having a resistance value Ri equal to the stage input impedance, series step resistors with resistance values Ri(1-A)/A and shunt step resistors with resistance values Ri/(1-A), where A is a step-to-step voltage attenuation factor. The input resistances of each step within a given stage are substantially equal, eliminating the need for output buffers at the step taps. A pair of switches are provided for each step, including an output switch connected between the step input node and a common output line, and a shunt switch connected in series with the shunt resistor for that step. Only one output switch is closed at a time, and only the corresponding shunt switch for the same step is opened. Multiple stages can be cascaded to provide a progressively finer voltage decremention, with the input impedance for each stage equal to the shunt resistance values for the preceding stage.