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:
Jan. 30, 2001
Filed:
Nov. 16, 1998
Nozomi Toki, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A D/A converter realizes an output analog signal with less ripple within a wide range and includes (a) a bit recognizer for recognizing at least one bit of a digital input signal to thereby produce a pulse width signal and a control signal; (b) a PWM signal generator for generating a PWM signal with a variable pulse width according to a value of the input signal by modulating the input signal according to a PWM process; and (c) an output circuit for outputting an output pulse voltage according to the value of the input signal. The pulse width of the PWM signal is controlled by the pulse width signal, and the output pulse voltage is controlled by the control signal. The pulse width of the PWM signal and the output pulse voltage are controlled in such a way that an area of a pulse of the PWM signal is equal to an area of every other pulse. Each pulse of the PWM signal may be divided into blocks having different values designed for forming a specific expansion characteristic.