By Topic

Reducing the power consumption in high-speed ΣΔ bandpass modulators

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

3 Author(s)
Cusinato, P. ; STMicroelectronics, Cornaredo, Italy ; Stefani, F. ; Baschirotto, A.

Power consumption is a key point in the design of high-speed switched capacitor (SC) circuits, which efficiently implement a number of analog functions. Among them, SC EA modulators are very popular for analog-to-digital conversion. In this kind of circuit, operational amplifiers are the most consuming cells because of their requirements in terms of dc-gain and unity-gain frequency. An operational amplifier with 90 dB de-gain and a unity-gain frequency of 250 MHz is presented. The large power consumption (18 mW) could make critical its use in commercial applications, in particular for portable devices. However, combining this cell with a fast adaptive biasing circuit, high performance may be achieved with a 40% power consumption reduction. This approach has been used in the design of a sixth-order bandpass ΣΔ modulator suitable for the conversion at intermediate frequency (10.7 MHz) of the FM radio signal. A comparison with a structure without the proposed solution demonstrates that the modulator performance are not degraded by the proposed technique.

Published in:

Circuits and Systems II: Analog and Digital Signal Processing, IEEE Transactions on  (Volume:48 ,  Issue: 10 )