Analysis of partial binary tree network (pbtn) for dynamic element matching (dem) digital to analog converter (dac)

Loading...
Thumbnail Image
Date
2016-03-01
Authors
Lim Ee Wey
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
In many digital systems, high performance DACs is essential to ensure proper operations. Matched components are required in order to achieve proper data conversion. Many factors such as process variation and temperature can cause components to be mismatched therefore it is impossible to fabricate perfectly matched components all the time. Mismatched components will lead to difference in designed values and actual values. One of the techniques to reduce the effect of mismatched components is to use Dynamic Element Matching (DEM) network to randomize the digital input codes to a DAC. This randomization can help to make the time averages of the equivalent components at each position to be nearly equal. The problem with existing DEM implementations is the linearity performance of the DAC is not as ideal and has glitches due to transitions of multiple switches at the same time. In this research, the implementation of 2 MSB randomization is proposed on a Partial Binary Tree Network (PBTN) DEM for a current-steering DAC and its performance evaluated in terms of glitches, DNL and INL. Comparison was done for 4-bit BTN, 4-bit PBTN and 4-bit (2 MSB) PBTN. Another comparison was done for performance for 6-bit & 8-bit (1 MSB) PBTN and 6-bit & 8-bit (2 MSB) PBTN DEM DAC. Simulation was done and the 8-bit (2 MSB) PBTN DEM DAC yields maximum glitch of 259.4 mV, DNL of 2.46 LSBs, and DNL of 31.00 LSBs.
Description
Keywords
Citation