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. 28, 1989
Filed:
Jan. 25, 1988
John F Stoops, Portland, OR (US);
Tektronix, Inc., Beaverton, OR (US);
Abstract
A current signal limiter provides precise minimum and maximum current limiting. Both maximum and minimum current limits are easily programmable. The signal limiter operates at maximum frequency response without inversion of the input signal. Current signal limiting is achieved by an NPN transistor biased in a common base configuration with the base coupled to a reference voltage source and the collector providing the output current, a series diode coupled to the emitter of the transistor for receiving a trickle current which prevents the transistor from turning off as well as setting a minimum current limit, and a diode matrix for receiving two reference currents and an input current. The diode matrix steers the input and reference currents to the transistor or to the reference voltage source, depending on the magnitude of the input and reference currents. The minimum and maximum current limits are programmable by adjusting the values of the reference currents and the trickle current.