Method and apparatus for start-up of analog-to-digital converters

US6970120B1 · kind B1 · utility

Assignee

• Nordic Semiconductor ASA · NO

Inventor

• Johnny Bjornsen · Trondheim, NO

Key dates

• Filing date: Jun 12, 2004
• Grant date: Nov 29, 2005
• Expiry date: Jun 12, 2024

Classification

• Technology area (CPC H): Electricity
• CPC primary: H03M3/414
• WIPO field: Basic communication processes
• WIPO sector: Electrical engineering

Abstract

An analog-to-digital (ADC) converter circuit that converts an analog input signal into a digital output circuit includes a calibration coefficient computation circuit for computing calibration coefficients of a calibration filter. The calibration coefficient computation circuit includes a switching device adapted to switch the analog input signal delivered to the ADC circuit between on and off states, and includes a pseudo-random signal generator adapted to input a pseudo-random signal to the ADC circuit. During a start-up phase of the ADC circuit, the ADC circuit, the switching device turns off the analog input signal to the ADC circuit, the pseudo-random signal generator inputs a pseudo-random signal into the ADC circuit, and the calibration coefficient computation circuit computes the calibration coefficients of the calibration filter. This ADC circuit configuration reduces startup time for the calibration filter to only a few clock cycles.