Polyphase Multifunction Energy Metering ICSilicon AnomalyADE7854/ADE7858/ADE7868/ADE7878 This anomaly list describes the known issues with the ADE7854, ADE7858, ADE7868, and ADE7878 silicon identified by the version register (Address 0xE707) being equal to 2, to 4, and to 5. Analog Devices, Inc., is committed, through future silicon revisions, to continuously improve silicon functionality. Analog Devices tries to ensure that these future silicon revisions remain compatible with your present software/systems by implementing the recommended workarounds outlined here. ADE7854/ADE7858/ADE7868/ADE7878 FUNCTIONALITY ISSUES Silicon Revision IdentifierChip MarkingSilicon StatusAnomaly SheetNo. of Reported Issues Version = 2 ADE7854ACPZ Released Rev. A 4 (er001, er002, er003, er004) ADE7858ACPZ ADE7868ACPZ ADE7878ACPZ Version = 4 ADE7854ACPZ Released Rev. B 1 (er005) ADE7858ACPZ ADE7868ACPZ ADE7878ACPZ Version = 5 ADE7854ACPZ Released Rev. C 1 (er005) ADE7858ACPZ ADE7868ACPZ ADE7878ACPZ FUNCTIONALITY ISSUES Table 1. Offset RMS Registers Cannot be Set to Negative Values [er001, Version = 2 Silicon] Background When the AIRMSOS, AVRMSOS, BIRMSOS, BVRMSOS, CIRMSOS, CVRMSOS, and NIRMSOS registers are set to a negative value, for sufficiently small inputs, the argument of the square root used in the rms data path may become negative. In this case, the corresponding AIRMS, AVRMS, BIRMS, BVRMS, CIRMS, or CVRMS rms register is automatically set to 0. Issue Negative values for the AIRMSOS, AVRMSOS, BIRMSOS, BVRMSOS, CIRMSOS, CVRMSOS, and NIRMSOS registers are not supported in the silicon version identified by the version register being equal to 2. Workaround Do not use negative values for the AIRMSOS, AVRMSOS, BIRMSOS, BVRMSOS, CIRMSOS, CVRMSOS, and NIRMSOS registers.