Application Note 1677 Authors: Oscar Mansilla, Richard Hood, Lawrence Pearce, Eric Thomson and Nick Vanvonno Single Event Effects Testing of the ISL70218SRH, Dual 36V Rad Hard Low Power Operation Amplifiers Introduction SEE Test Objective The intense heavy ion environment encountered in space applications can cause a variety of transient and destructive effects in analog circuits, including single-event latch-up (SEL), single-event transients (SET) and single-event burnout (SEB). These effects can lead to system-level failures including disruption and permanent damage. For a predictable and reliable system operation, these components have to be formally designed and fabricated for SEE hardness. Then followed by a detailed SEE testing to validate the design. This report discusses the results of SEE testing of Intersil’s ISL70218SRH. The objectives of SEE testing on the ISL70218SRH were to evaluate its susceptibility to single event latch-up and single event burnout and characterize its SET behavior over various LET levels. Reference Documents SEE Test Facility 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. • ISL70218SRH Data Sheet, FN7871 SEE Test Procedure Product Description The part was tested for single event latch-up and burnout, using Au ions (LET = 86.4MeV/mg/cm2) and single event transient using Ne, Ar, and Kr ions. The ISL70218SRH is a dual, low-power precision amplifier optimized for single-supply applications. This op amp features a common mode input voltage range extending to 0.5V below the V- rail, a rail-to-rail differential input voltage range, and rail-to-rail output voltage swing, which makes it ideal for single-supply applications where input operation at ground is important. The ISL70218SRH is implemented in an advanced bonded wafer SOI process using deep trench isolation, resulting in a fully isolated structure. This choice of process technology also results in latch-up free performance, whether electrically or single-event (SEL) caused. This amplifier is designed to operate over a single supply range of 3V to 36V or a split supply voltage range of +1.8V/-1.2V to ±18V. The combination of precision and small footprint provides the user with outstanding value and flexibility relative to similar competitive parts. Applications for these amplifiers include precision active filters, low noise front ends, loop filters, data acquisition and charge amplifiers. The part is packaged in a 10 Ld Hermetic Ceramic Flat Pack and operates over the extended temperature range of -55°C to +125°C. A summary of key full temperature range specifications follows: The device under test (DUT) was mounted in the beam line and irradiated with heavy ions of the appropriate species. The parts were assembled in 10 lead dual in-line packages with the metal lid removed for beam exposure. The beam was directed onto the exposed die and the beam flux, beam fluence and errors in the device outputs were measured. The tests were controlled remotely from the control room. All input power was supplied from portable power supplies connected via cable to the DUT. The supply currents were monitored along with the device outputs. All currents were measured with digital ammeters, while all the output waveforms were monitored on a digital oscilloscope for ease of identifying the different types of SEE, which the part displayed. Events were captured by triggering on changes in the output. SEE Test Set-Up Diagrams A schematic of the evaluation board is shown in Figure 1. RF RIN- IN- IN- - 10k RIN+ IN+ • Input Offset Voltage . . . . . . . . . . . . . . . . . . . . . . . 290µV, max. + IN - IN + VCM VREF IN+ + ISL70218SRH (1/2) 100k VP V+ 0 VOUT VVM 10k RREF+ 100k • Offset Voltage Drift . . . . . . . . . . . . . . . . . . . . . . . 1µV/°C, max. • Input Offset Current . . . . . . . . . . . . . . . . . . . . . . . . 75nA, max. • Input Bias Current . . . . . . . . . . . . . . . . . . . . . . . . . 800nA, max. • Supply Current/Amplifier . . . . . . . . . . . . . . . . . . . 1.4mA, max. VREF GND FIGURE 1. SIMPLIFIED SEE SCHEMATIC • Gain Bandwidth Product . . . . . . . . . . . . . . . . . . . . . 4MHz, typ. October 21, 2011 AN1677.0 1 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas Inc. 2011. 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. Application Note 1677 Each operational amplifier was set up in a non-inverting operation with G = 11V/V. The IN- inputs were grounded and the input signal was applied to the IN+ pin. Cross-section Calculation Cross sections are calculated as shown by Equation 1: (EQ. 1) CS (LET) = N/F where: • CS is the SET cross section (cm²), expressed as a function of the heavy ion LET • LET is the linear energy transfer in MeV.cm²/mg, corrected according to the incident angle, if any. Single Event Transient Testing Test Method Biasing used for SET test runs was VS = ±4.5V and ± 18V. Similar to SEL/B testing, a DC voltage of 200mV was applied to the non-inverting inputs of the amplifiers. Signals from the switch board in the control room were connected to two LECROY oscilloscopes: one set to capture transients due to the output of channel A and the other to capture transients on the output of channel B. SET events are recorded when movement on output during beam exposure exceeds the set window trigger of ±80mV. Summary of the scope settings are: a. Scope 1 is set to trigger on Channel 1 to a OUTA window of ±80mV. Measurements on Scope 1 are: CH1 = OUTA 200mV/div, CH2 = OUTA 500mV/div, CH3 = OUTB 200mV/div, CH4 = OUT5 500mV/div. • N is the total number of SET events • F is fluence in particles/cm², corrected according to the incident angle, if any. b. Scope 2 is set to trigger on Channel 3 to a OUTB window of ±80mV. Measurements on Scope 1 are: CH1 = OUTA 200mV/div, CH2 = OUTA 500mV/div, CH3 = OUTB 200mV/div, CH4 = OUT5 500mV/div. A value of 1/F is the assumed cross section when no event is observed. Single Event Latch-up and Burnout Results The first testing sequence looked at destructive effects due to burnout or latch-up. A burnout condition is indicated by a permanent change in the device supply current after application of the beam. If the increased current is reset by cycling power, it is termed a latch-up. No burnout or latch-up was observed using Au ions (LET = 86.4MeV · cm2/mg) at 0° incidence from the perpendicular. Testing was performed on four parts at +125°C (case temperature) and up to the maximum voltage, VS = ±18.2V. The first two parts (part ID 1&2) commenced testing with VS = ±15V and on subsequent tests VS voltage was increased to ±17.5V and then ±18.2V. All other parts were tested with a VS of ±17.5V and ±18.2V. All test runs were run to a fluence of 2x106/cm2. A power supply applied a DC voltage of 200mV to the non-inverting inputs of the amplifiers during the test. Functionality of all outputs was verified after exposure. IDD and IEE was recorded pre and post exposure, with 5% resolution. Results are shown in Table 1 for the 36.4V total supply voltage. The switch board at the end of the 20-ft cabling was found to require terminations of 10nF to keep the noise on the waveforms to a minimum. Cross Section Results Compared to other Intersil radiation tolerant circuits, the ISL70218SRH was not designed for single event transient mitigation. The best approach to characterize the single event transient response is to represent the data on a LET threshold plot. Figure 2 shows the cross section of the IC versus the LET level, at VS = ±4.5V and ± 18V. It can be seen that for an LET < 20MeV· cm2/mg, the cross section is nearly the same independent of supply voltage. As the linear energy transfer increases, there is noticeable increases in cross section area with a higher supply voltage. Data from Figure 2 is represented in Table 2. Figures 3 through 6 show the cross section of each channel independently at VS = ±4.5V and ± 18V with confidence interval bars for a 90% confidence level. TABLE 1. ISL70218SRH DETAILS OF SEB/L TESTS FOR VS = ±18.2V and LET = 86.4MeV · cm2/mg TEMP (°C) +125 +125 +125 +125 LET (MeV.cm^2/mg) 86 86 86 86 SUPPLY CURRENT PREEXPOSURE (mA) 3.8 3.8 4.0 3.8 SUPPLY CURRENT POSTEXPOSURE (mA) LATCH EVENTS CUMULATIVE FLUENCE (PARTICLES/cm2) CUMULATIVE CROSS SECTION (cm2) DEVICE SEB/L 0 2.0 x 106 5.0 x 10-7 1 PASS 0 2.0 x 106 5.0 x 10-7 2 PASS 0 2.0 x 106 5.0 x 10-7 3 PASS 3.7 0 2.0 x 106 5.0 x 10-7 4 PASS TOTAL EVENTS 0 3.7 3.8 3.9 OVERALL FLUENCE 8.0 x 106 OVERALL CS 1.25 x 10-7 TOTAL UNITS 2 4 AN1677.0 October 21, 2011 Application Note 1677 ϰ͘ϱϬͲϬϰ ϰ͘ϬϬͲϬϰ ϯ͘ϱϬͲϬϰ ϯ͘ϬϬͲϬϰ Ϯ͘ϱϬͲϬϰ Ϯ͘ϬϬͲϬϰ ϭ͘ϱϬͲϬϰ ϭ͘ϬϬͲϬϰ /^>ϳϬϮϭϴ^Z,s^сц ϰ͘ϱs ϱ͘ϬϬͲϬϱ /^>ϳϬϮϭϴ^Z,s^сц ϭϴs Ϭ͘ϬϬнϬϬ Ϭ ϭϬ ϮϬ ϯϬ ϰϬ ϱϬ ϲϬ >d;DĞsͼĐŵϮͬŵŐͿ FIGURE 2. CROSS SECTION OF THE ISL70218SRH vs LINEAR ENERGY TRANSFER VS. SUPPLY VOLTAGE TABLE 2. DETAILS OF THE CROSS SECTION OF THE ISL70218SRH vs LET vs SUPPLY VOLTAGE SUPPLY VOLTAGE (V) ION ANGLE (°) EFF LET (cm2/mg) FLUENCE PER RUN (PARTICLES/cm2) NUMBER OF RUNS TOTAL EVENTS EVENT CS cm^2 ±4.5V Ne 0 2.7 2.0 x 106 4 13 1.63 x 10-6 ±4.5V Ar 0 8 2.0 x 106 3 53 8.83 x 10-6 4 391 4.89 x 10-5 ±4.5V Ar 60 17 2.0 x 106 ±4.5V Kr 0 28 2.0 x 106 4 1097 1.37 x 10-4 ±4.5V Kr 60 56 2.0 x 106 4 1579 1.97 x 10-4 ±18V Ne 0 2.7 2.0 x 106 4 25 3.13 x 10-6 ±18V Ne 60 5.4 2.0 x 106 4 148 1.85 x 10-6 ±18V Ar 0 8 2.0 x 106 4 123 1.54 x 10-6 ±18V Ar 60 17 2.0 x 106 4 390 4.88 x 10-5 4 1655 2.07 x 10-4 4 3410 4.26 x 10-4 ±18V Kr 0 28 2.0 x 106 ±18V Kr 60 56 2.0 x 106 3 AN1677.0 October 21, 2011 ϭ͘ϰϬͲϬϰ ϭ͘ϰϬͲϬϰ ϭ͘ϮϬͲϬϰ ϭ͘ϮϬͲϬϰ ϭ͘ϬϬͲϬϰ ϭ͘ϬϬͲϬϰ ƌŽƐƐ^ĞĐƚŝŽŶ;ĐŵϮͿ ƌŽƐƐ^ĞĐƚŝŽŶ;ĐŵϮͿ Application Note 1677 ϴ͘ϬϬͲϬϱ ϲ͘ϬϬͲϬϱ ϰ͘ϬϬͲϬϱ ϴ͘ϬϬͲϬϱ ϲ͘ϬϬͲϬϱ ϰ͘ϬϬͲϬϱ ŚĂŶŶĞů Ϯ͘ϬϬͲϬϱ ŚĂŶŶĞů Ϯ͘ϬϬͲϬϱ Ϭ͘ϬϬнϬϬ Ϭ͘ϬϬнϬϬ Ϭ ϭϬ ϮϬ ϯϬ ϰϬ ϱϬ ϲϬ Ϭ ϭϬ ϮϬ >d;DĞsͬŵŐͬĐŵϮͿ FIGURE 3. CHANNEL A CROSS SECTION VS. LET FOR V S = ±4.5V WITH 90% CONFIDENCE LEVEL INTERVAL BARS ϰϬ ϱϬ ϲϬ FIGURE 4. CHANNEL B CROSS SECTION VS. LET FOR V S = ±4.5V WITH 90% CONFIDENCE LEVEL INTERVAL BARS ϯ͘ϬϬͲϬϰ Ϯ͘ϱϬͲϬϰ Ϯ͘ϱϬͲϬϰ Ϯ͘ϬϬͲϬϰ Ϯ͘ϬϬͲϬϰ ƌŽƐƐ^ĞĐƚŝŽŶ;ĐŵϮͿ ƌŽƐƐ^ĞĐƚŝŽŶ;ĐŵϮͿ ϯϬ >d;DĞsͬŵŐͬĐŵϮͿ ϭ͘ϱϬͲϬϰ ϭ͘ϬϬͲϬϰ ϭ͘ϬϬͲϬϰ ϱ͘ϬϬͲϬϱ ŚĂŶŶĞů ϱ͘ϬϬͲϬϱ ϭ͘ϱϬͲϬϰ Ϭ͘ϬϬнϬϬ ŚĂŶŶĞů Ϭ͘ϬϬнϬϬ Ϭ ϭϬ ϮϬ ϯϬ ϰϬ ϱϬ ϲϬ >d;DĞsͬŵŐͬĐŵϮͿ FIGURE 5. CHANNEL A CROSS SECTION VS. LET FOR V S = ±18V WITH 90% CONFIDENCE LEVEL INTERVAL BARS Ϭ ϭϬ ϮϬ ϯϬ ϰϬ ϱϬ ϲϬ >d;DĞsͬŵŐͬĐŵϮͿ FIGURE 6. CHANNEL B CROSS SECTION VS. LET FOR V S = ±18V WITH 90% CONFIDENCE LEVEL INTERVAL BARS Transient Response The ISL70218SRH features rail to rail output, as such, it was expected SETs would cause the output to rail out. Surprisingly the majority of the transients were less than 10% of output voltage. Duration of the transients range in the 10’s of µs to 100’s of µs. Figures 7 though 28 represent output waveforms of the amplifiers under test at various bias conditions and LET values. The plots are composites of the first 25 transients captured on the scope. This information is useful in quantifying the excursion of the output as a result of SEE induced transients. Worst voltage transient seen is a 300mV excursion and longest SET duration is 1.6ms (see Figure 19). 4 AN1677.0 October 21, 2011 Application Note 1677 Typical SET Captures FIGURE 7. TYPICAL CAPTURE AT VS = ±4.5V, CHANNEL A, LET = 2.7MeV/mg/cm2, RUN 432 FIGURE 8. TYPICAL CAPTURE AT VS = ±4.5V, CHANNEL B, LET = 2.7MeV/mg/cm2, RUN 430 FIGURE 9. TYPICAL CAPTURE AT VS = ±18V, CHANNEL B, LET = 2.7MeV/mg/cm2, RUN 429 FIGURE 10. TYPICAL CAPTURE AT VS = ±18V, CHANNEL A, LET = 2.7MeV/mg/cm2, RUN 433 5 AN1677.0 October 21, 2011 Application Note 1677 Typical SET Captures (Continued) FIGURE 11. TYPICAL CAPTURE AT VS = ±18V, CHANNEL A, LET = 5.6MeV/mg/cm2, RUN 431 FIGURE 12. TYPICAL CAPTURE AT VS = ±18V, CHANNEL B, LET = 5.6MeV/mg/cm2, RUN 432 FIGURE 13. TYPICAL CAPTURE AT VS = ±4.5V, CHANNEL A, LET = 8.5MeV/mg/cm2, RUN 405 FIGURE 14. TYPICAL CAPTURE AT VS = ±4.5V, CHANNEL B, LET = 8.5MeV/mg/cm2, RUN 405 6 AN1677.0 October 21, 2011 Application Note 1677 Typical SET Captures (Continued) FIGURE 15. TYPICAL CAPTURE AT VS = ±18V, CHANNEL A, LET = 8.5MeV/mg/cm2, RUN 406 FIGURE 16. TYPICAL CAPTURE AT VS = ±18V, CHANNEL B, LET = 8.5MeV/mg/cm2, RUN 406 FIGURE 17. TYPICAL CAPTURE AT VS = ±4.5V, CHANNEL A, LET = 17MeV/mg/cm2, RUN 403 FIGURE 18. TYPICAL CAPTURE AT VS = ±4.5V, CHANNEL B, LET = 17MeV/mg/cm2, RUN 403 7 AN1677.0 October 21, 2011 Application Note 1677 Typical SET Captures (Continued) FIGURE 19. TYPICAL CAPTURE AT VS = ±18V, CHANNEL A, LET = 17MeV/mg/cm2, RUN 404 FIGURE 20. TYPICAL CAPTURE AT VS = ±18V, CHANNEL B, LET = 17MeV/mg/cm2, RUN 404 FIGURE 21. TYPICAL CAPTURE AT VS = ±4.5V, CHANNEL A, LET = 28MeV/mg/cm2, RUN 511 FIGURE 22. TYPICAL CAPTURE AT VS = ±4.5V, CHANNEL B, LET = 28MeV/mg/cm2, RUN 511 8 AN1677.0 October 21, 2011 Application Note 1677 Typical SET Captures (Continued) FIGURE 23. TYPICAL CAPTURE AT VS = ±18V, CHANNEL A, LET = 28MeV/mg/cm2, RUN 512 FIGURE 24. TYPICAL CAPTURE AT VS = ±18V, CHANNEL B, LET = 28MeV/mg/cm2, RUN 512 FIGURE 25. TYPICAL CAPTURE AT VS = ±4.5V, CHANNEL A, LET = 56MeV/mg/cm2, RUN 513 FIGURE 26. TYPICAL CAPTURE AT VS = ±4.5V, CHANNEL B, LET = 56MeV/mg/cm2, RUN 513 9 AN1677.0 October 21, 2011 Application Note 1677 Typical SET Captures (Continued) FIGURE 27. TYPICAL CAPTURE AT VS = ±18V, CHANNEL A, LET = 56MeV/mg/cm2, RUN 514 FIGURE 28. TYPICAL CAPTURE AT VS = ±18V, CHANNEL B, LET = 56MeV/mg/cm2, RUN 514 Summary Single Event Transient Single Event Burnout/Latch-up Based on the results presented, the ISL70218SRH op amp offers advantages over the competitor’s part with respect to maximum SET output voltage excursion. No transient pulses > 0.5V were observed at LET levels up to MeV · cm2/mg. Both the voltage level and duration of transients were proportional to LET. The maximum transients at an LET of 56 MeV · cm2/mg were observed to be ~ 300mV with a typical duration no > 200µs (see Figure 27). The longest transient duration observed was at an LET of 17 MeV · cm2/mg with an out of scale transient > 300mV and length of the transient was > 1.6ms. No single event burnout (SEB) was observed for the device up to an LET value of MeV · cm2/mg (+125°C) and voltage supply of VS = ± 18.2V. No single event latch-up (SEL) were observed for the device up to an LET value of MeV · cm2/mg (+125°C). voltage supply of VS = ± 18.2V. 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 Application Note or Technical Brief is current before proceeding. For information regarding Intersil Corporation and its products, see www.intersil.com 10 AN1677.0 October 21, 2011