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:
Feb. 22, 2000
Filed:
Oct. 31, 1997
Garry C Gillette, San Jose, CA (US);
Credence Systems Corporation, Fremont, CA (US);
Abstract
A current sense circuit for use in a semiconductor tester has a voltage source for forcing a voltage to a first node of the current sense circuit, a current sense resistor having a first terminal connected to the first node and a second terminal connected to a second node for connection to a pin of a device under test (DUT), and a differential amplifier for measuring voltage drop across the current sense resistor. The current sense resistor is composed of a network of switchable semiconductor resistor devices each having at least a first resistance state and a second resistance state, in which the resistor device has first and second different resistance values respectively, and a device for selectively controlling the states of the resistor devices, whereby the resistance value of the current sense resistor can be selectively varied.