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:
Sep. 21, 2004
Filed:
Jun. 03, 2003
James R. Hochschild, Plano, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
An improved sigma-delta modulation technique that may be employed in a sigma-delta Digital-to-Analog Converter (DAC) to convert digital signals into corresponding analog signals over a wide signal range and with high linearity. The sigma-delta DAC comprises a sigma-delta modulator including a variable quantizer and a quantizer controller, and an internal DAC. The sigma-delta modulator adaptively quantizes the digital input signal to a first number p of quantization levels. Next, the quantizer controller controls the variable quantizer to correlate the p quantization levels to the amplitude of the digital input signal, thereby generating a second number q of quantization levels. The internal DAC then receives the q quantization levels from the variable quantizer one group of p levels at a time, and produces an analog output signal therefrom that corresponds to the digital input signal.