ON-BOARD FERRITE CORE MEMORIES WITH MEGABIT CAPACITY

Abstract

For intermediate data storage in scientific satellites a ferrite core buffer memory with a capacity of 0.5 . . 2 Mbit was developed as a replacement of the hitherto used magnetic tape memories. For this memory a 3 D-organization with a pulse program especially adapted for buffer use was applied. For the realization of the access-circuitry multichip semiconductors in hermetically sealed flatpacks were combined with tantalum thin film resistor networks. A new small volume rugged memory stack was used. The cores used had an outer diameter of 0.5 mm. For this system a new flexible equipment practice is used which leads to a high component density. Furthermore, a 0.5 Mbit random access ferrite core memory was developed for the Helios satellite. This satellite will go into orbit in June 1974. The prototype model has a mass of 4.5 kg, overall dimensions of 194 x 210 x 207 mm, a volume of 7.08 W. (432 cu. inch) and has a power consumption of 2 Watts in stand-by and of 4.8 Watts at a bit rate of 16 kbit/s. It works satisfactorily within a temperature range of -45 to +75° C.