公开(公告)号：US10348319B1

公开(公告)日：2019-07-09

申请号：US15983658

申请日：2018-05-18

Applicant: Analog Devices Global Unlimited Company

Inventor： Sandeep Monangi ,  Anoop Manissery Kalathil ,  Vinayak Mukund Kulkarni ,  Michael C. W. Coln

IPC: H03M1/06 ,  H03M1/08

Abstract: Techniques to use reservoir capacitors in ADC to supply most of the charge to bit-trial capacitors as bit-trials are performed. An accurate reference voltage source, e.g., a reference buffer circuit, only needs to supply the difference, e.g., an inaccuracy, in the charge supplied by the reservoir capacitors. Instead of having to resettle for each bit-trial, the accurate reference voltage source has only to deliver the initial charge to the reservoir capacitors during acquisition and once more when the ADC is ready to sample onto the residue amplifier. These techniques can ease the demands on the reference buffer circuit and requirement of external decoupling capacitors, for example.

公开(公告)号：US10122376B2

公开(公告)日：2018-11-06

申请号：US15711176

申请日：2017-09-21

Applicant: Analog Devices Global

Inventor： Anoop Manissery Kalathil ,  Arvind Madan ,  Sandeep Monangi

IPC: H03M1/12 ,  H03M1/46 ,  H03M1/14 ,  H03M1/80

Abstract: Systems and methods to reduce the amount of reference current drawn by a SAR ADC by including an auxiliary or precharge reference source. The ADC can connect the bit trial capacitors of a main digital-to-analog converter (DAC) to an auxiliary or precharge reference source during the loading of the bit trials, and then the ADC can switch to a main reference buffer. After allowing enough time for both phases, the main DAC can proceed with the bit trials to resolve the remaining bits. The rest of the bit trials can be performed directly using the main reference buffer.