ISL71030M

6. Radiation Tolerance

R34DS0006EU0101 Rev.1.01

Page 21 of 24

Apr 12, 2021

6.2

Single-Event Effects Testing

The intense heavy ion environment encountered in space applications can cause a variety of Single-Event Effects

(SEE). SEE can lead to system-level performance issues including disruption, degradation, and destruction. For

predictable and reliable space system operation, individual electronic components should be characterized to

determine their SEE response. The following is a summary of the ISL71030M SEE testing.

6.2.1 SEE Test Facility

Testing was performed at the Texas A&M University (TAMU) Cyclotron Institute heavy ion facility on April 3, 2019.

The overall test setup includes the test jig containing four evaluation boards mounted and wired through a 20ft

cable to the data room. The end of the 20ft cable in the data room was connected to a switchboard. The

switchboard was wired to the power supplies and monitoring equipment/scopes.

6.2.2 SEE Test Setups

Testing the ISL71030M parts for damaging SEE (Single Event Burnout (SEB) and Single Event Latch-Up (SEL))

had the parts configured to select input 13 by applying the test voltage, VTEST, to address lines A2 and A3 and

GND to A0, A1, and EN-bar. This connected IN-13 to the output. The output was loaded with a 10kΩ resistor to

GND, and the input (IN-13) had a 10kΩ resistor to the test voltage, VTEST. This created a resistor divider that put

the output, OUT, at half of VTEST. The test voltage, VTEST, was also applied to the supply, V+, and to the inputs

9 to 16, excluding 13. The inputs 1 to 8 had GND applied to them. The parts tested for damaging SEE were

heated with a thin-film heater on the back of the PCB to attain a case temperature of 125°C.

Single Event Transients (SET) were tested with VTEST at 3.00V and 5.50V, the extremes of the suggested

operating range. For SET the parts were not heated and therefore were at the ambient of about 25°C. The

definition of a SET was a ±20mV movement of OUT from its nominal value of half VTEST. As with the SEB

testing, the part was configured to select input 13. However, unlike the SEB testing, the addressing was done with

applied voltages of 70% VREF on A2 and A3, and 30% VREF applied to A0, A1, and EN-bar. This was done to

place the addressing at low noise margin states as VREF was set to 3.00V. OUT had a 10kΩ resistor to GND and

IN 13 was supplied with VTEST through a 10kΩ resistor to again set OUT to half of VTEST.

6.2.3 Single Event Burnout and Latch-Up (SEB/L) Results

The test voltage, VTEST, was sequentially set to 6.50V, 6.75V, and 7.00V for three independent irradiations on

four parts. Before and after each irradiation the total current to V+ and VREF was measured along with the output

voltage, OUT. No deviations greater than 3% were registered for the currents, and no deviation of even 1% was

seen on OUT. The conclusion was that no permanent damage resulted from the irradiations as done.

6.2.4 SET Results

No SET were captured with the ±20mV criterion in the most recent testing. This result is inconsistent with previous

testing on a similar part. In the earlier testing, the ±20mV SET corresponded to cross sections of 419µm2 at

VTEST = 3.0V and 2020µm2 at VTEST = 5.5V. However, the nature of the SET captures was that a spike

transient triggered the capture at ±20mV but the low frequency motion on the OUT node without the spike was

less than ±20mV. Examples are presented below from the previous testing. Thus, the captures previously were

dependent on the high-frequency coupling. A slight change in this could have dropped the SET below the trigger

point for the newer testing. Because there are no SET to examine for the newer testing, this is all supposition.

However, the older testing still represents a worst case estimate of the ISL71030M SET behavior. The previous

testing did provide evidence that the ±20mV SET vanished at an LET of 20MeV·cm2/mg. This should also apply

to the ISL71030M.