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. 03, 1998
Filed:
Jun. 19, 1996
Mark R Vitunic, San Jose, CA (US);
Daniel D Culmer, San Jose, CA (US);
Micro Linear Corporation, San Jose, CA (US);
Abstract
A signal generator generates a reference signal, centered about a reference voltage and having a predetermined period. The signal generator also generates output signals P and Z. The output signal P is a squarewave which changes levels at the peaks of the reference signal. The output signal Z is a squarewave which changes levels at the reference voltage crossings of the reference signal. A phase-shifted signal generator generates a phase-shifted signal using the output signals P and Z by switching in appropriate signal levels from the signal generator. The output signals P and Z are input to a switch control circuit which controls a network of switches, depending on a current region of the reference signal, to couple appropriate signals to an amplifier circuit. The switch control circuit determines the current region based on the state of the output signals P and Z. The amplifier circuit provides the phase-shifted signal in response to the signals coupled to it by the network of switches. In an alternate embodiment, the output signal Z is generated by a hysteretic comparator and changes levels at positive and negative threshold levels above and below the reference voltage. The values of the positive and negative threshold values are variable and determine the degree of phase shift between the phase-shifted signal and the reference signal.