Test Report 016 Single Event Effects (SEE) Testing of the ISL71830SEH 5V 16:1 Multiplexer Introduction SEE Test Objectives The intense proton and heavy ion environment encountered in space applications can cause a variety of Single Event Effects (SEE) in electronic circuitry, including Single Event Upset (SEU), Single Event Transient (SET), Single Event Functional Interrupt (SEFI), Single Event Burnout (SEB) and Single Event Gate Rupture (SEGR). 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. This report discusses the results of SEE testing performed on the ISL71830SEH 16:1 analog multiplexer product for space applications. The ISL71830SEH was tested to determine its susceptibility to single event burnout and gate rupture (SEB as used here refers to either destructive ion effect) and to characterize its single event transient (SET) behavior. The SEB testing looked operating voltages at an LET of 60MeV*cm2/mg that bounded a safe operating region. The SET testing looked for LET that have sufficient energy to generate an SET of a small size (±20mV) on the output of the multiplexer. Testing was performed on samples from the lot J69526.1 manufactured in Intersil’s proprietary P6SOI process. Product Description Testing was performed at the Texas A&M University (TAMU) Cyclotron Institute heavy ion facility. This facility is coupled to a K500 super-conducting cyclotron, which is capable of generating a wide range of test particles with the various energy, flux and fluence levels needed for advanced radiation testing. Details on the test facility can be found on the TAMU Cyclotron website (http://cyclotron.tamu.edu/). Testing was carried out on December 15th and 16th of 2014 and March 20th of 2015. The ISL71830SEH discussed here is a 5V, 16:1 analog multiplexer fabricated in Intersil’s proprietary P6SOI process. This product was designed with both Total Ionizing Dose (TID) and SEE in mind and has unique design provisions for mitigating effects of both radiation sources. The ISL71831SEH is a 32:1 multiplexer built of the same circuit blocks as the ISL71830SEH and is considered a circuit extension of the ISL71830SEH but is reported on separately. Product Documentation ISL71830SEH datasheet Standard Microcircuit Drawing (SMD): 5962-15247 September 21, 2015 TR016.0 1 SEE Test Facility SEE Test Set-up SEE testing was carried out with the sample in an active configuration. A schematic of the ISL7830SEH SEE test fixture is shown in Figure 1. The test circuit configuration was set to address input 13 which, was consequently routed to the output. Switch 1 (SW1) allowed addressing to be selected between rail biasing (SW1 open) or logic threshold biasing (SW1 closed). The inputs were broken into three groupings (inputs 1 to 8 were tied to GND, input 13, and inputs 9 to 12 combined with inputs 14 to 16 and were tied to supply V+). The splitting of the inputs into GND and V+ allowed for bidirectional biasing of the unselected inputs CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas LLC 2015. All Rights Reserved Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries. All other trademarks mentioned are the property of their respective owners. Test Report 016 V+ IS V+ 1 28 OUT NC 2 27 NC NC 3 26 IN 8 IN 16 4 25 IN 7 IN 15 5 24 IN 6 IN 14 6 23 IN 5 IN 13 7 22 IN 4 IN 12 8 21 IN 3 IN 11 9 20 IN 2 IN 10 10 19 IN 1 IN 9 11 18 ENABLE GND 12 17 ADDR A0 VREF 13 16 ADDR A1 ADDR A3 14 15 ADDR A2 VOUT 10k VIN13 IIN13 10k VREF IREF 1k SW1 1.33k 70% VREF with SW1 closed, VREF when open 30% VREF with SW1 closed, GND when open 1k With SW1 closed the address lines are set to 30% and 70% of VREF, the logic thresholds for minimum noise margin. With SW1 OPEN the address lines are set to VREF and GND for maximum noise margin. VOUT is set to be ½ VIN13 by the two series 10kΩ resistors. FIGURE 1. SCHEMATIC OF THE ISL71830SEH SEE TEST CIRCUIT Submit Document Feedback 2 TR016.0 September 21, 2015 Test Report 016 SEB Testing of the ISL71830SEH The first set of SEB (destructive SEE) testing was carried out as summarized in Table 1. The output voltage along with the supply and reference currents were monitored for changes indicative of damage to the part. Four parts were tested in pairs through the condition sequence of increasing supply and input voltages. This SEB testing was done with Pr at 10° incidence for an effective surface LET = 60MeV*cm2/mg. The Pr ions have a range into silicon of 110µm with a Bragg range of 37µm. This puts the LET Bragg peak well below the active device region and into the handle wafer of the SOI. Each irradiation was to an effective fluence of 5x106 ions/cm2 with a case temperature of +125°C ±10°. Significant changes in readings over the irradiations are indicated by shaded entry cells in Table 1. The SEB data indicates that ISL71830SEH at an LET = 60MeV*cm2/mg did not suffer damage at supply and input voltage of 6.5V. DUT 4 did see a 12% increase in supply current at 6.5V, but this was not considered indicative a damage as the other increases noted constituted much larger increases. Catastrophic damage was noted on DUT2 at 6.75V but not on the other units at 6.75V and 7.0V. Safe operating range is so limited to 6.5V at an LET = 60MeV*cm2/mg. TABLE 1. ISL71830SEH SEB MONITOR PARAMETER TEST RESULTS (Note 1) SEB TESTS AT LET = 60MeV*cm2/mg VOUT (1%) IS (10%) IVREF (10%) V+ (V) VREF (V) VIN13 (V) APPROX. VOUT (V) PRE (V) POST (V) PRE (nA) POST (nA) PRE (nA) POST (nA) 6.50 6.50 6.50 3.250 3.243 3.241 1323 1316 25 25 DUT 2 3.238 3.238 94.9 99 22 23 DUT 3 3.239 3.238 1708 1731 28 29 DUT 4 3.238 3.238 1995 2240 34 34 3.366 3.366 1463 1457 26 26 DUT 2 3.364 3.366 97 124µA 24 24 DUT 3 3.364 3.364 1918 1898 30 31 DUT 4 3.364 3.364 2490 2450 36 36 3.491 3.491 1603 1590 28 38 DUT 2 3.490 3.490 212µA 199µA 25 25 DUT 3 3.489 3.488 2100 2111 32 33 DUT 4 3.488 3.488 2700 2730 37 38 DUT 1 DUT 1 DUT 1 6.75 7.00 6.75 7.00 6.75 7.00 3.375 3.500 NOTE: 1. Samples were tested in pairs (DUT 1 and DUT 2 and DUT 3 and DUT 4) in the indicated sequence of conditions. Irradiation was with Pr at 10º incidence for effective LET = 60MeV*cm2/mg with the case temperature at +125ºC ±10ºC and to a fluence of 5x106 ions/cm2 for each test. Shaded entries indicate changes in excess of the change criteria at the column heads. Submit Document Feedback 3 TR016.0 September 21, 2015 Test Report 016 SET Testing of the ISL71830SEH The objective of this SET testing was to look for SET disruptions on the output (pin 28, VOUT) of the operating ISL71830SEH. The biasing was arranged to provide addressing at the input logic thresholds of 70% and 30% of the VREF (2.1V and 0.9V at VREF = 3V). These settings provide minimal noise margin against SET events. The unselected inputs (1-12, and 14-16) were connected to one of the supply rail voltages while input 13 was connected to the positive supply through a 10kΩ resistor with another 10kΩ resistor from VOUT to GND. This ensured a significant change in VOUT should an address change be induced or instantaneous connection to a rail be induced by an ion impact. A ±20mV trigger on VOUT was used to indicate and capture an SET. Testing began at LET = 86MeV*cm2/mg and continued at LET = 43 and LET = 20MeV*cm2/mg. The results in Table 2 indicate that no SET of greater than 20mV deviation were generated for the testing run with LET = 20MeV*cm2/mg and significantly fewer SET greater than 20mV were generated at LET = 43MeV*cm2/mg as compared to LET = 86MeV*cm2/mg. The SET data was post processed to select out the twenty largest deviations (for both positive and negative extreme deviations) and the twenty longest durations (for both positive and negative extreme deviations) for plotting as in Figure 2 for the case of LET = 86MeV*cm2/mg. Of the 80 possible SET not all are unique as the largest deviations are often also the longest durations. From Figure 2 it can be seen that the SET observed at V+ = 3V and LET = 86MeV*cm2/mg were uniformly less than 75mV peak excursion and had decay time constants on the order of 5µs so that the SET essentially disappeared in 15µs from the SET initiation. The RC decay magnitudes appear to peak at about -50mV and +25mV. The RC decay time is dominated by the 700pF of the monitor cable and the 5kΩ of equivalent resistance driving VOUT to its nominal level. Figure 3 displays the composite plots for the case of V+ = 5.5V and LET = 86MeV*cm2/mg. In these cases the peak excursions just exceed 100mV with slightly larger RC decay magnitudes than seen at V+ = 3V. The slightly larger SET magnitudes are in line with the increase in V+ from 3V to 5.5V so that the SET magnitudes seem linked to the supply rails as anticipated. Again the RC decay back to nominal VOUT is within 15µs. Figure 4 displays the composite plots for the case of V+ = 3V and LET = 43MeV*cm2/mg. In these cases the peak excursions are under 50mV with RC decay magnitudes less than 25mV. In Figure 5 the trend toward larger SET with the higher V+ of 5.5V is seen again, but the magnitudes are significantly less than seen at LET = 86MeV*cm2/mg. The trend toward smaller SET is completed at LET = 20MeV*cm2/mg where no SET of greater than the ±20mV trigger criteria were captured. This does not imply a lack of SET but rather a limitation on the size of SET. TABLE 2. TABLE FOR SET EXCEEDING ±20mV AT MINIMAL ADDRESSING CONDITIONS (Note 2) TEST CONDITIONS: LET in MeV*cm2/mg SET COUNTS FOR ±20mV TRIGGER V+, VIN13 (V) VREF (V) APPROX. VOUT (V) DUT 1 DUT 2 DUT 3 DUT 4 CROSS SECTION (cm2) CLOSED 3.0 3.0 1.50 296 410 -- 288 8.28x10-5 CLOSED 5.5 3.0 2.75 226 234 216 219 5.59x10-5 CLOSED 3.0 3.0 1.50 29 19 11 8 4.19x10-6 CLOSED 5.5 3.0 2.75 89 83 59 92 2.02x10-5 CLOSED 3.0 3.0 1.50 0 0 -- -- <1.25x10-7 CLOSED 5.5 3.0 2.75 0 0 -- -- <1.25x10-7 SW1 Au LET0º = 86 Ag LET0º = 43 Cu LET0º = 20 NOTE: 2. SW1 = closed is logic thresholds. Each indicated irradiation was done to a fluence 4x106 ion/cm2. Submit Document Feedback 4 TR016.0 September 21, 2015 Test Report 016 FIGURE 2A. FIGURE 2B. FIGURE 2C. FIGURE 2. Composite plot of 20 largest and longest SET for both positive and negative deviations. DUT 1, 2 and 4 at LET = 86MeV*cm2/mg and V+ = 3V. DUT 3 had AC noise obliterating the SET indicative of a poor contact, so it was omitted. Submit Document Feedback 5 TR016.0 September 21, 2015 Test Report 016 FIGURE 3A. FIGURE 3B. FIGURE 3C. FIGURE 3D. FIGURE 3. Composite plot of 20 largest and longest SET for both positive and negative deviations. DUT 1-4 AT LET = 86MeV*cm2/mg and V+ = 5.5V. Submit Document Feedback 6 TR016.0 September 21, 2015 Test Report 016 FIGURE 4A. FIGURE 4B. FIGURE 4C. FIGURE 4D. FIGURE 4. Composite plot of 20 largest and longest SET for both positive and negative deviations. DUT 1-4 at LET = 43MeV*cm2/mg and V+ = 3V. Submit Document Feedback 7 TR016.0 September 21, 2015 Test Report 016 FIGURE 5A. FIGURE 5B. FIGURE 5C. FIGURE 5D. FIGURE 5. Composite plot of 20 largest and longest SET for both positive and negative deviations. DUT 1-4 at LET = 43MeV*cm2/mg and V+ = 5.5V. Conclusions No SEE damage (within 12% increase in supply current) was observed on the four units tested at 6.5V supply and inputs with ions of effective LET = 60MeV*cm2/mg. The testing was done at +125°C case temperature. A unit registered catastrophic damage at 6.75V. Three units survived at 7.0V with no apparent changes due to irradiation there. It must be concluded that safe operation at effective LET = 60MeV*cm2/mg is limited to 6.5V. Further testing is planned to look at the 6V to 6.8V range for better resolution on the limits of damaging SEE. SET testing of the ISL71830SEH demonstrated only small SET (just over 100mV peak) at LET = 86MeV*cm2/mg. At the 20mV trigger, the SET cross section was less than 1x10-4 cm2 for LET = 86MeV*cm2/mg. At LET = 43MeV*cm2/mg the cross section for ±20mV events dropped to about 2x10-5 cm2 with the maximum peak deviations under 50mV. At LET = 20MeV*cm2/mg no SET reached the ±20mV trigger threshold corresponding to a nominal cross section of <1.25x10-7 cm2 for ±20mV events. In all cases the RC decay dominated by the 700pF of cable load on VOUT and the 10kΩ resistors to VIN13 and GND allowed the SET to die out in 15µs. Extrapolating from the test conditions, the SET magnitudes toward the farthest rail could roughly double for signals nominally near either of the two rails, V+ or GND. It is also reasonable to assume different recovery times for different VOUT loading and source resistance from the selected VINxx. For example, a 100pF load on VOUT and a 1kΩ source resistance should result in a SET recover in under 1µs. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that the document is current before proceeding. For information regarding Intersil Corporation and its products, see www.intersil.com Submit Document Feedback 8 TR016.0 September 21, 2015