A comparison of nonvolatile memory technologies for spacecraft applications

A generic application for nonvolatile mass memory on the order of 2 Gb is discussed for space applications. This system would be large enough to store satellite data for readout to the ground over readout sites. The memory should be block-addressable, so it can be used as a magnetic disk replacement. It is concluded that only 4-Mb magnetic bubble memories are currently able to replace spaceborne magnetic tape recorders for gigabit-size memories, with no penalty in size and only 50% higher weight. Since bubble memories have longer inherent life than tape recorders, additional size and weight savings could result. As far as EEPROMs (electronically erasable programmable read-only memories) are concerned, a lightweight, 2-Gb memory will have to await development of wafer-scale integration. Otherwise, the 2000 to 16000 separate chips required to supply two gigabits of storage require excessive complexity of fabrication and wiring.<>