# US 2014/0197972 A1 · Successive approximation register analog-to-digital converter and conversion time calibration method thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0197972 A1 - Document ID: US20140197972A1 - Status: Published application - Kind: A1 - Application number: 14/055,413 - Filed: 2013-10-16 - Published: 2014-07-17 - Earliest claimed: 2013-01-14 - Assignees: Realtek Semiconductor Corp. - Applicants: Realtek Semiconductor Corporation - Inventors: Jian-ru LIN; Yu-Chang CHEN; Shin-syong HUANG - Web page: https://patentgrep.com/patent/US20140197972A1 ## CPC - H03M 1/06: Continuously compensating for, or preventing, undesired influence of physical parameters (periodically, {e.g. by using stored correction values,} H03M1/10) - H03M 1/462: {Details of the control circuitry, e.g. of the successive approximation register} - H03M: CODING; DECODING; CODE CONVERSION IN GENERAL (using fluidic means F15C4/00; optical analogue/digital converters G02F7/00; coding, decoding or code conversion, specially adapted for particular applications, see the relevant subclasses, e.g. G01D, G01R, G06F, G06T, G09G, G10L, G11B, G11C, H04B, H04L, H04M, H04N; ciphering or deciphering for cryptography or other purposes involving the need for secrecy G09C) ## Abstract A successive approximation register analog-to-digital converter and a conversion time calibration method thereof are provided. The successive approximation register analog-to-digital converter includes a conversion circuit and a conversion time calibration apparatus. The conversion circuit has a conversion time under a process, voltage, and temperature (PVT) variation. The conversion time calibration apparatus is configured to detect a conversion time condition and adjust the conversion time of the conversion circuit according to the conversion time condition. ## Claims ### Claim 1 A conversion time calibration method for use in a successive approximation register analog-to-digital converter, the successive approximation register analog-to-digital converter comprising a conversion circuit and a conversion time calibration apparatus, and the conversion circuit having a conversion time under a process, voltage, and temperature (PVT) variation, the conversion time calibration method comprising the following steps of: (a) detecting a conversion time condition of the conversion circuit by the conversion time calibration apparatus; and (b) adjusting the conversion time of the conversion circuit by the conversion time calibration apparatus according to the conversion time condition. ### Claim 2 (depends on 1) The conversion time calibration method as claimed in claim 1, wherein the conversion circuit is configured to transform an analog voltage into an N-bit digital voltage in N correction periods, and N is a positive integer; and wherein the step (a) of the conversion time calibration method further comprises the following step of: (a1) detecting the conversion time condition of the conversion circuit by the conversion time calibration apparatus according to the Nth correction period of the conversion circuit. ### Claim 3 (depends on 1) The conversion time calibration method as claimed in claim 1, wherein the conversion circuit is further electrically connected to a digital circuit; and wherein the step (a) of the conversion time calibration method further comprises the following step of: (a1) detecting the conversion time condition of the conversion circuit by the conversion time calibration apparatus according to a signal-to-noise and distortion ratio measured by the digital circuit. ### Claim 4 (depends on 1) The conversion time calibration method as claimed in claim 1, wherein the step (a) of the conversion time calibration method further comprises the following step of: (a1) detecting the conversion time condition of the conversion circuit by the conversion time calibration apparatus according to a comparison of an oscillation period with the conversion time of the conversion circuit which is detected. ### Claim 5 (depends on 1) The conversion time calibration method as claimed in claim 1, wherein the conversion circuit comprises a comparison circuit, and the comparison circuit comprises a comparer and a controller electrically connected to the comparer; and wherein the step (b) of the conversion time calibration method further comprises the following step of: (b1) changing a delay time between the comparer and the controller by the conversion time calibration apparatus according to the conversion time condition to adjust the conversion time of the conversion circuit. ### Claim 6 (depends on 1) The conversion time calibration method as claimed in claim 1, wherein the step (b) further comprises the following step of: (b1) changing one of an operating voltage and an operating current of the successive approximation register analog-to-digital converter by the conversion time calibration apparatus according to the conversion time condition to adjust the conversion time of the conversion circuit. ### Claim 7 (depends on 1) The conversion time calibration method as claimed in claim 1, wherein the conversion time condition indicates that the conversion time is shorter than a rated conversion time, and the conversion time calibration apparatus adjusts the conversion circuit according to the conversion time condition to increase the conversion time to the rated conversion time. ### Claim 8 (depends on 1) The conversion time calibration method as claimed in claim 1, wherein the conversion time condition indicates that the conversion time is longer than a rated conversion time, and the conversion time calibration apparatus adjusts the conversion circuit according to the conversion time condition to decrease the conversion time to the rated conversion time. ### Claim 9 (depends on 4) The conversion time calibration method as claimed in claim 4, wherein the step (b) further comprises the following step of: (b1) changing one of an operating voltage and an operating current of the successive approximation register analog-to-digital converter by the conversion time calibration apparatus according to the conversion time condition to adjust the conversion time of the conversion circuit. ### Claim 10 (depends on 4) The conversion time calibration method as claimed in claim 4, wherein the conversion circuit comprises a comparison circuit, and the comparison circuit comprises a comparer and a controller electrically connected to the comparer; and wherein the step (b) of the conversion time calibration method further comprises the following step of: (b1) changing a delay time between the comparer and the controller by the conversion time calibration apparatus according to the conversion time condition to adjust the conversion time of the conversion circuit. ### Claim 11 A successive approximation register analog-to-digital converter, comprising: a conversion circuit, having a conversion time under a PVT variation; and a conversion time calibration apparatus, being configured to detect a conversion time condition of the conversion circuit and adjust the conversion time of the conversion circuit according to the conversion time condition. ### Claim 12 (depends on 11) The successive approximation register analog-to-digital converter as claimed in claim 11, wherein the conversion circuit is configured to transform an analog voltage into an N-bit digital voltage in N correction periods, and N is a positive integer; and wherein the conversion time calibration apparatus is configured to detect the conversion time condition of the conversion circuit according to the Nth correction period of the conversion circuit. ### Claim 13 (depends on 11) The successive approximation register analog-to-digital converter as claimed in claim 11, wherein the conversion circuit is further electrically connected to a digital circuit and the conversion time calibration apparatus is configured to detect the conversion time condition of the conversion circuit according to a signal-to-noise and distortion ratio measured by the digital circuit. ### Claim 14 (depends on 11) The successive approximation register analog-to-digital converter as claimed in claim 11, wherein the conversion time calibration apparatus is configured to detect the conversion time condition of the conversion circuit according to a comparison of an oscillation period and the conversion time of the conversion circuit which is detected. ### Claim 15 (depends on 11) The successive approximation register analog-to-digital converter as claimed in claim 11, wherein the conversion circuit comprises a comparison circuit including a comparer and a controller electrically connected to the comparer, and the conversion time calibration apparatus is further configured to change a delay time between the comparer and the controller according to the conversion time condition to adjust the conversion time of the conversion circuit. ### Claim 16 (depends on 11) The successive approximation register analog-to-digital converter as claimed in claim 11, wherein the conversion time calibration apparatus is further configured to change one of an operating voltage and an operating current of the successive approximation register analog-to-digital converter according to the conversion time condition to adjust the conversion time of the conversion circuit.