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Initial Radiation Report On the Chip Express CX2041

Prepared by: R. Katz (NASA/GSFC) and A. Feizi (J&T)
Test Date: August 1997 (TID), September 1997 (SEE)
Test Facilities: TID - NASA/GSFC
SEE - Brookhaven National Laboratory

Initial SEE Test of the CX2041

Two sample Chip Express CX2041’s were irradiated at DOE/BNL in September 1997. The RAM sections of the CX2041’s were not used and the parts were biased at either VCC = 4.5 VDC or VCC = 5.5 VDC and were at nominal temperatures. All runs were 107 ions/cm2 unless terminated by a latchup.


Both devices performed similarly and latched when exposed to Titanium with a LET = 22 MeV-cm2/mg. Neither device latched at LET = 18.8 MeV-cm2/mg. The upset cross-section was small at LET = 18.8 MeV-cm2/mg and averaged 4 x 10-10 cm2/flip-flop.


The charts below show ICC strip charts of the latchups. Note that the power supply used was programmed with an 800 mA current limit which automatically shut down the test and protected the part from damage.


Here’s a summary of the test runs:


Run #

Date/Time

DeviceID

Ion

Energy MeV

Range um

LET(Si) MeV.cm2/mg

Tilt deg

Fluence #/cm2/sec

35

26Sep97 00:00

CX1

Ti-48

227.0

47.5

18.8

0.0

6.301E+04

37

26Sep97 00:03

CX1

Ti-48

227.0

40.5

22

31.5

5.323E+04

36

26Sep97 00:01

CX1

Ti-48

227.0

33.6

26.5

45.0

4.607E+04

10

25Sep97 21:15

CX1

Br-79

290.0

37.3

37.1

0.0

1.061E+05

11

25Sep97 21:16

CX1

Br-79

290.0

37.3

37.1

0.0

1.207E+04

38

26Sep97 00:11

CX2

Ti-48

227.0

47.5

18.8

0.0

6.358E+04

40

26Sep97 00:15

CX2

Ti-48

227.0

40.5

22

31.5

5.503E+04

39

26Sep97 00:12

CX2

Ti-48

227.0

33.6

26.5

45.0

4.862E+04

12

25Sep97 21:23

CX2

Br-79

290.0

37.3

37.1

0.0

1.231E+04

 

Initial TID Test of the CX2041

 

 

A sample Chip Express CX2041 was irradiated at NASA/GSFC in the Cobalt-60 source. The dose rate was 5 krads (Si) / day and ICC was measured in situ. Testing proceeded until 14 krads (Si).

 

Figure 1 shows a plot of ICC vs. dose. The identical data is presented on two scales to show both the performance of the device over the 14 krad (Si) exposure and its behavior at lower doses where the supply currents are more reasonable. The "steps" between 1 and 2 mA in the high resolution plot, for example, are an artifact of the power supply (HP6624A) used for current monitoring and is digitization noise.

 

As can be seen from the graph, the device gave a good response until approximately 7 to 8 krads (Si), when the supply current started to rapidly increase. A functional test was performed on the sample approximately 17 hours after being removed from both the radiation chamber and bias. The device passed functional tests and device currents did decrease. Here’s a summary:

 

 

Pre-Rad

Post 14 krad (Si)

static

0

110.0

clock network

4.7

114.3

dynamic

12.7

123.4

 

Presently, the device is undergoing continuous functional tests with no errors and the currents continue to decrease but are still significantly higher than nominal.


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Last Revised: February 03, 2010
Digital Engineering Institute
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