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Test Synopsis V. 1.0

31-Dec-96

Heavy Ion SEL Results on ATMEL FPGA

Heavy ion single event latchup (SEL) testing was performed at BNL on June 6, 1996 on the following devices:

MFR     Device   Part #      Date Code   Other Markings   Vcc
ATMEL   FPGA     AT6002-JC   9512        4D065904         5V

Additional device information is as follows:

                                               Configuration
Device      Package       Process       Epi    RAM in bits     Usable Gates/ Test Design
AT6002-JC   84-pin PLCC   0.8 um CMOS   10um   64Kx1(8Kused)   2000/1024 stage shift reg.

The largest members of the family is:
- ATMEL AT6010 - 10000 usable gates

All devices are RAM-based programmable devices with schematic configurations downloaded via an EPROM external to the device.

Test modes used were:
- AT6002-JC
- Dynamic: While being irradiated, a 100kHz clock is fed through a chain of 1024 stage shift register.

Ions used for testing were:

   Ion     Energy    LET at normal incidence	
   F-19    140 MeV   3.38 MeV*cm2/mg
   Si-28   186 MeV   7.88 MeV*cm2/mg
   Cl-35   208 MeV   11.4 MeV*cm2/mg
   Ni-58   266 MeV   26.5 MeV*cm2/mg

Intermediate LET values were gained by varying the device to the beam angle of incidence. Testing was performed at room temperature at a Vcc of 5V.

Test Results

SEL
Latchup was observed as shown in figure 1. The LETth is approximately 10 for a fluence of 1E7.

All SELs on the ATMEL device were recoverable with power resets. Nominal operating Icc was around 60 mA. SEL currents were between 197-302 mA.

Discussion

Based on the proton testing performed in March 1996, SEU heavy ion testing performed in April 1996, and this SEL heavy ion testing described herein, these devices are not recommended for usage in most space missions. They would be grouped in GSFC's category 4 rating: Not recommended for general usage, but may be used as long as extensive SEU mitigation and SEL mitigation techniques be employed.