Radiation Test Results for ISSI 1 Gb DDR2

Abstract

ISSI IS46DR16640B and IS46DR81280B DDR2 1Gb devices are studied for radiation effects. Special emphasis is placed on understanding the device-level behavior and recovery of various error modes. An overview of all identified key radiation degradation and disruptions are provided. This includes TID and SEE. Key results are presented for standard SBU, MBU, SEFI, stuck bits, and TID performance. For the case of device-level disruptions (such as SEFIs that cause the device to stop responding), recovery requirements are explored to assist users in recovering operation without power-cycling. Power cycling was not necessary for any observed SEFI mode. The established ratio of SEFIs that may require power cycle to all SEFIs is below 0.0037. SEFIs are seen to have controller-dependent signatures with some controller architectures suppressing some, or all, of the erroneous data delivered during a SEFI.