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Rad Hard 20 Megabit (512K x 40-Bit) EEPROM MCM Memory

Discontinued Product. Please contact the factory for the latest replacement.


Part Number(s): 79C2040

DDC's 79C2040 multi-chip module (MCM) memory features a greater than 100 krad (Si) total dose tolerance, dependent upon orbit. Using DDC's patented radiation-hardened RAD-PAK® MCM packaging technology, the 79C2040 is the first radiation-hardened 20 megabit MCM EEPROM for space application. The 79C2040 uses twenty 1 Megabit high speed CMOS die to yield a 20 megabit product. The 79C2040 is capable of in-system electrical byte and page programmability. It has a 128 word page programming function to make the erase and write operations faster. It also features Data Polling and a Ready/Busy signal to indicate the completion of erase and programming operations. In the 79C2040, hardware data protection is provided with the RES pin, in addition to noise protection on the WE signal and write inhibit on power on and off. Software data protection is implemented using the JEDEC optional standard algorithm.

DDC's patented RAD-PAK® packaging technology incorporates radiation shielding in the microcircuit package. It eliminates the need for box shielding while providing the required radiation shielding for a lifetime in orbit or space mission. In a GEO orbit, RAD-PAK provides greater than 100 krad (Si) radiation dose tolerance. This product is available with screening up to DDC's self-defined Class K.


  • RAD-PAK® radiation-hardened against natural space radiation
  • Total dose hardness:
    • >100 krad (Si)
    • Dependent upon orbit
  • Excellent Single event effects
    • SELTH > 120 MeV/mg/cm2
    • SEU > 90 MeV/mg/cm2 read mode
    • SEU = 18 MeV/mg/cm2 write mode
  • High endurance
    • 10,000 cycles/byte (Page Programming Mode)
    • 10 year data retention
  • Page Write Mode: 128 Dword Page
  • High Speed:
    • 150 and 200 ns maximum access times
  • Automatic programming
    • 10 ms automatic Page/Dword write
  • Low power dissipation
    • 375 mW/MHz active current
    • 3.2 mW standby current




79C2040 20 Megabit (512K x 40-Bit) EEPROM MCM Data Sheet

 Application Note

EEPROM Frequently Asked Questions


How Rad Hard Do You Need? The Changing Approach To Space Parts Selection?

Proton Transport An Examination of Model and Experimental Data For Space Environment Protons

 Generic Document

DDC Custom Solutions Brochure

DDC Product Catalog

DDC Corporate Overview


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