US 12,261,620 B2
Methods and apparatus to capture switch charge injections and comparator kickback effects
Rajashekar Goroju, Bangalore (IN); Prasanth K, Bangalore (IN); Dileepkumar Ramesh Bhat, Bangalore (IN); Rakul Viswanath, Bangalore (IN); Sravana Kumar Goli, Bangalore (IN); and Rahul Sharma, Bangalore (IN)
Assigned to Texas Instruments Incorporated, Dallas, TX (US)
Filed by Texas Instruments Incorporated, Dallas, TX (US)
Filed on Mar. 31, 2023, as Appl. No. 18/129,604.
Claims priority of application No. 202241074406 (IN), filed on Dec. 22, 2022.
Prior Publication US 2024/0213998 A1, Jun. 27, 2024
Int. Cl. H03M 1/38 (2006.01); H03M 1/06 (2006.01); H03M 1/08 (2006.01); H03M 1/16 (2006.01); H03M 1/46 (2006.01); H03M 1/80 (2006.01)
CPC H03M 1/38 (2013.01) [H03M 1/0607 (2013.01); H03M 1/0818 (2013.01); H03M 1/164 (2013.01); H03M 1/468 (2013.01); H03M 1/804 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A device comprising:
capacitive digital to analog converter (C-DAC) circuitry including switches configured to transition between an open state and a closed state responsive to switch signals; and
controller circuitry configured to provide the switch signals to cause the C-DAC circuitry to:
configure the switches into a first configuration to sample a differential analog input signal, wherein configuring switches into a first configuration includes: (a) a transition of a first switch and a second switch to the closed state, and (b) a transition of a third switch to the open state;
configure the switches into a second configuration to convert the sample into a digital value, wherein configuring switches into a second configuration includes: (a) a transition of the first switch and the second switch to the open state, and (b) a transition of the third switch to the closed state;
configure the switches into a third configuration to discharge a capacitor in the C-DAC circuitry, wherein configuring switches into the third configuration includes a transition of the first switch and the second switch to the closed state, wherein configuring switches into the third configuration begins an Auto Zero (AZ) phase with the third switch in the closed state;
configure the switches into a fourth configuration to repeat the transition of the third switch to the open state corresponding to the first configuration;
configure the switches into a fifth configuration to repeat the transition of the first switch and the second switch to the open state corresponding to the second configuration;
configure the switches into a sixth configuration to repeat the transition of the third switch to the closed state corresponding to the second configuration; and
perform an AZ decision with the switches in the sixth configuration.