# US 10,310,049 B2 · Semiconductor device and failure detection method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,310,049 B2 - Document ID: US10310049B2 - Status: Granted - Kind: B2 - Application number: 15/218,006 - Filed: 2016-07-23 - Published: 2017-02-16 - Granted: 2019-06-04 - Earliest claimed: 2015-08-10 - Assignees: Renesas Electronics Corporation - Applicants: Renesas Electronics Corporation - Inventors: Yuichi Okuda; Hideo Nakane; Takaya Yamamoto; Keisuke Kimura; Takashi Oshima - Web page: https://patentgrep.com/patent/US10310049B2 ## CPC - G01R 35/00: Testing or calibrating of apparatus covered by the other groups of this subclass - G01R 19/2509: {Details concerning sampling, digitizing or waveform capturing} - H03M 1/10: Calibration or testing - H03M 1/1038: {by storing corrected or correction values in one or more digital look-up tables (H03M1/1057 takes precedence)} - H03M 1/1076: {Detection or location of converter hardware failure, e.g. power supply failure, open or short circuit} - H03M 1/468: {in which the input S/H circuit is merged with the feedback DAC array} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - 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 The present invention provides a semiconductor device and a failure detection method capable of detecting an excessive variation among elements that constitute an analog circuit as a failure. According to an embodiment, a semiconductor device 1 includes: an AD converter 11; a digital assist circuit 12 that corrects an error of a digital signal Do corresponding to an analog signal Ain processed by the AD converter 11; and a failure detection circuit 13 that detects whether the AD converter 11 has a failure based on a correction amount by the digital assist circuit. The semiconductor device 1 is therefore able to detect the excessive variation among the elements that constitute the AD converter 11 as a failure. ## Claims ### Claim 1 A semiconductor device, comprising: an analog circuit; a digital assist circuit that corrects an error of a digital signal corresponding to an analog signal processed by the analog circuit; and a failure detection circuit that detects whether the analog circuit has a failure based on a correction amount by the digital assist circuit, wherein the failure detection circuit detects a failure by evaluating one of: whether a weight coefficient Eo exceeds a predesignated threshold; whether a deviation from an average amount of the weight coefficient Eo exceeds a predesignated threshold; whether a radix (a ratio of weight coefficients of adjacent bits) of an AD converter exceeds a predesignated threshold; and whether a p-radix (an addition or subtraction of weight coefficients of adjacent bits) of the AD converter exceeds a predesignated threshold. ### Claim 2 (depends on 1) The semiconductor device according to claim 1, wherein the failure detection circuit determines that the analog circuit has a failure when the correction amount is larger than a predetermined threshold. ### Claim 3 (depends on 1) The semiconductor device according to claim 1, wherein the failure detection circuit determines that the analog circuit has a failure when a difference between the correction amount and an initial correction amount, which is the correction amount before the analog circuit is used in a normal operation, is larger than a predetermined threshold. ### Claim 4 (depends on 3) The semiconductor device according to claim 3, further comprising a storage unit that stores the initial correction amount. ### Claim 5 (depends on 4) The semiconductor device according to claim 4, wherein the storage unit is a programmable nonvolatile memory. ### Claim 6 (depends on 3) The semiconductor device according to claim 3, wherein the initial correction amount is stored in a storage unit outside of the semiconductor device. ### Claim 7 (depends on 1) The semiconductor device according to claim 1, wherein: the analog circuit is an analog-to-digital (AD) converter; and the digital assist circuit corrects a non-linear error of the digital signal output from the AD converter corresponding to the analog signal input to the AD converter. ### Claim 8 (depends on 1) A semiconductor system comprising: The semiconductor device according to claim 1; and a higher system that performs predetermined processing for the semiconductor device based on the result of the detection of the failure output from the semiconductor device. ### Claim 9 A failure detection method, comprising: correcting an error of a digital signal corresponding to an analog signal processed by an analog circuit using a digital assist circuit; and detecting whether the analog circuit has a failure based on a correction amount by the digital assist circuit, wherein the digital assist circuit comprises: a weight coefficient calculation unit; and a correction unit. ### Claim 10 (depends on 9) The failure detection method according to claim 9, wherein it is determined that the analog circuit has a failure when the correction amount is larger than a predetermined threshold. ### Claim 11 (depends on 9) The failure detection method according to claim 9, wherein it is determined that the analog circuit has a failure when a difference between the correction amount and an initial correction amount, which is the correction amount before the analog circuit is used in a normal operation, is larger than a predetermined threshold. ### Claim 12 (depends on 11) The failure detection method according to claim 11, further comprising storing the initial correction amount in a storage unit provided on a same semiconductor chip on which the analog circuit is mounted. ### Claim 13 (depends on 12) The failure detection method according to claim 12, wherein the storage unit is a programmable nonvolatile memory. ### Claim 14 (depends on 11) The failure detection method according to claim 11, further comprising storing the initial correction amount in a storage unit provided on a semiconductor chip different from a semiconductor chip on which the analog circuit is mounted. ### Claim 15 (depends on 7) The semiconductor device according to claim 7, wherein the digital assist circuit corrects a non-linear error of the digital signal output by determining and providing a correction amount Eo of a weight coefficient of the AD converter, and wherein the failure detection circuit detects whether the analog circuit has a failure based on whether the correction amount Eo is larger than a predetermined threshold. ### Claim 16 (depends on 7) The semiconductor device according to claim 7, wherein a variation of elements constituting the AD converter provides a radix<2. ### Claim 17 A semiconductor device, comprising: an analog circuit a digital assist circuit that corrects an error of a digital signal corresponding to an analog signal processed by the analog circuit; and a failure detection circuit that detects whether the analog circuit has a failure based on a correction amount by the digital assist circuit, wherein the analog circuit comprises an analog-to-digital (AD) converter and wherein a variation of elements constituting the AD converter is smaller than 0.5 of a least significant bit (LSB) of the AD converter. ### Claim 18 (depends on 1) The semiconductor device according to claim 1, wherein the analog circuit comprises one of: a successive approximation analog-to-digital (AD) converter; a pipeline type AD converter; a flash type AD converter; and an analog circuit in which a correction can be performed by the digital assist circuit.