Single Event Effects (SEE) Testing of the ISL7457SRH Non-Inverting, Quad CMOS Driver September 2009 Introduction The intense, heavy ion environment encountered in space applications can cause a variety of effects in electronic circuitry, including Single Event Transient (SET), Single Event Latchup (SEL) and Single Event Burnout (SEB). These Single Event Effects (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 ISL7457SRH non-inverting, quad CMOS driver. Product Description The ISL7457SRH is a monolithic, non-inverting, quad CMOS driver fabricated on a BiCMOS junction isolated process. The ISL7457SRH has a Total Ionizing Dose (TID) capability of 10 krads(Si) at both high and low dose rates. Functionally, the ISL7457SRH is a high speed, non-inverting, quad CMOS driver featuring 2 A peak drive currents and tri-stable outputs. Typical applications include clock/line driver, CCD driver and level-shifter. SEE Test Objectives The ISL7457SRH was tested for SEE to determine its susceptibility to SEL/SEB and to characterize its SET behavior. SEE Test Facility Testing was performed at the Texas A&M University 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. SEE Test Plan A schematic of the ISL7457SRH SEE test circuit is shown in Figure 1. The inputs to the A and B drivers were tied to VS though a 10 kΩ resistor, so the A and B driver outputs were normally high. The inputs to the C and D drivers were tied to ground, so the C and D driver outputs were normally low. Also, the outputs of the A and B drivers were tied to VS through 1 kΩ resistors, while the outputs of the C and D drivers were tied to ground through 1 kΩ resistors. In this circuit configuration, a transient on any of the driver outputs caused the VS supply current to increase, which was detected by measuring an increase in voltage drop 1 across diode, D1. Average supply voltage and average supply current were monitored using digital multimeters. The voltage across D1 and all four driver outputs were monitored using digitizing oscilloscopes. The voltage across D1 provided the trigger source for all testing. All connections from the test circuit to the test equipment were made through approximately 20 feet of coaxial cable. R2 U2 R1 VS INA VS+ OE OUTA INB OUTB VL GND R1 D1 R1 NC ISL7457SRH VH NC OUTC INC OUTD IND VS- R1 R1 C1 C1 D1 R1 R2 = = = = 100n 1N4148 1k 10k Figure 1: ISL7457SRH SEE Test Circuit Schematic Table 1 shows the beam characteristics used during SEE testing. Ion Incident LET Species Angle (MeV/mg/cm2) (°) Au 0 85.4 Ag 0 42.2 Ag 48.2 43.2 Ag 60 43.2 LETeff Flux Fluence (MeV/mg/cm2) (ions/cm2/s) (ions/cm2) 1 x 104 1 x 104 1 x 104 1 x 104 85.4 42.2 64.8 86.4 1.95 x 106 3.9 x 106 2 x 106 2 x 106 Effective Fluence (ions/cm2) 1.95 x 106 3.9 x 106 1.33 x 106 1 x 106 Table 1: Beam Characteristics Neutron irradiated devices were used for some of the SEE tests in hopes of improving SEL performance. Neutron irradiation reduces the gain of parasitic bipolar transistors that are implicated in latchup. Characteristics of the neutron irradiation are shown in Table 2. 2 Energy Fluence (MeV) (neutrons/cm2) 1.0 (silicon equivalent) 3 x 1013 * Package anneal removes ~2/3 of the neutron damage Effective Fluence* (neutrons/cm2) 1 x 1013 Table 2: Neutron Irradiation Characteristics Table 3 shows the SEE tests that were performed. A transient was defined to be a movement of > 50% of the supply voltage on a driver output that was detected as a ~100 mV change in voltage drop across D1. Test ID 120 Ion Species Au LETeff Test 2 (MeV/mg/cm ) Conditions 85.4 Per Figure 1 schematic, VS = 15 V, TC = 25˚C 122 Au 85.4 Per Figure 1 schematic, VS = 15 V, TC = 25˚C 123 Au 85.4 Per Figure 1 schematic, VS = 15 V, TC = 25˚C 231 Ag 42.2 Per Figure 1 schematic, VS = 15 V, TC = 25˚C 232 Ag 42.2 Per Figure 1 schematic, VS = 15 V, TC = 25˚C 233 Ag 42.2 Per Figure 1 schematic, VS = 15 V, TC = 25˚C 234 Ag 42.2 Per Figure 1 schematic, VS = 15 V, TC = 25˚C 105 Ag 64.8 Per Figure 1 schematic, VS = 14.7 V, TC = 85˚C, neutron irradiated device 107 Ag 64.8 Per Figure 1 schematic, VS = 14 V, TC = 85˚C, neutron irradiated device 104 Ag 86.4 Per Figure 1 schematic, VS = 6.1 V, TC = 125˚C, neutron irradiated device 108 Ag 86.4 Per Figure 1 schematic, VS = 6.1 V, TC = 125˚C, neutron irradiated device 106 Ag 86.4 Per Figure 1 schematic, VS = 6.1 V, TC = 125˚C, neutron irradiated device 109 Ag 86.4 Per Figure 1 schematic, VS = 6.1 V, TC = 125˚C, neutron irradiated device 111 Ag 86.4 Per Figure 1 schematic, VS = 6.1 V, TC = 125˚C, neutron irradiated device * Not Applicable due to device failure. Table 3: SEE Tests 3 Transient Count NA* NA* NA* 12 11 12 12 NA* NA* 78 96 97 89 84 Au Ion Testing (LETeff = 85.4 MeV/mg/cm2) Three devices were irradiated with Au ions at an LETeff = 85.4 MeV/mg/cm2, a flux of 1 x 104 ions/cm2/s, VS = 15 V and TC = 25˚C. The target effective fluence for each test was 1.95 x 106 ions/cm2. All three devices failed after less than one minute of irradiation, so actual effective fluence was < 6 x 105 ions/cm2. After failure, average supply current on all three devices increased from ~ 1 mA to > 800 mA. Prior to failure, some spiking of the supply current was observed, but this did appreciably affect the level of the driver outputs. Numerous short (< 500 ns) low-high-low transients were observed on the C and D driver outputs. Also, a few longer duration (> 18 us) high-low transients were observed on the A and B driver outputs. Ag Ion Testing (LETeff = 42.2 MeV/mg/cm2) Four devices were irradiated with Ag ions at an LETeff = 42.2 MeV/mg/cm2, a flux of 1 x 104 ions/cm2/s, VS = 15 V and TC = 25˚C. The effective fluence during irradiation was 3.9 x 106 ions/cm2. There was negligible change in average supply current after testing, indicating no permanent damage was incurred. Some spiking of the supply current was observed, but this did not appreciably affect the level of the driver outputs. Numerous short (< 500 ns) low-high-low transients were observed on the outputs of the C and D drivers. The cross section of the device was computed by dividing the total number of transients observed for all four devices by the total effective fluence seen by all four devices. Therefore, cross section = total number of transients / total effective fluence = 47 / 15.6 x 106 ions/cm2 = 3.01 x 10-6 cm2. Ag Ion Testing (LETeff = 64.8 MeV/mg/cm2) One neutron irradiated device was irradiated with Ag ions at an LETeff = 64.8 MeV/mg/cm2, a flux of 1 x 104 ions/cm2/s, VS = 14.7 V and TC = 85˚C. The target effective fluence for the test was 1.33 x 106 ions/cm2. The device failed after 67 s, so actual effective fluence was 4.04 x 105 ions/cm2. After failure, average supply current increased from < 1 mA to ~6 mA. One neutron irradiated device was irradiated with Ag ions at an LETeff = 64.8 MeV/mg/cm2, a flux of 1 x 104 ions/cm2/s, VS = 14 V and TC = 85˚C. The target effective fluence for the test was 1.33 x 106 ions/cm2. The device failed after 132 s, so actual effective fluence was 8.58 x 105 ions/cm2. After failure, average supply current increased from < 1 mA to ~600 mA. Ag ion Testing (LETeff = 86.4 MeV/mg/cm2) Five neutron irradiated devices were irradiated with Ag ions at an LETeff = 86.4 MeV/mg/cm2, a flux of 1 x 104 ions/cm2/s, VS = 6.1 V and TC = 125˚C. The effective fluence during irradiation was 1 x 106 ions/cm2. There was negligible change in average supply current after testing, indicating no permanent damage was incurred. Some spiking of the supply current was observed, but this did not appreciably affect the level of the driver outputs. Numerous short (< 500 ns) low-high-low transients were observed on the outputs 4 of the C and D drivers. The cross section of the device was computed by dividing the total number of transients observed for all five devices by the total effective fluence seen by all five devices. Therefore, cross section = total number of transients / total effective fluence = 444 / 5 x 106 ions/cm2 = 8.88 x 10-5 cm2. Summary (Non-neutron Irradiated Devices) When tested with Au ions at an LET = 85.4 MeV/mg/cm2, VIN = 15 V, TC = 25˚C, the ISL7457SRH was found to be vulnerable to SEL/SEB. When tested with Ag ions at an LET = 42.2 MeV/mg/cm2, VIN = 15 V, TC = 25˚C, the ISL7457SRH was found to be immune to SEL/SEB. SET behavior consisted of numerous low-high-low transients at the outputs of the C and D drivers that lasted for < 500ns. The capture cross section was computed to be 3.01 x 10-6 cm2. Summary (Neutron Irradiated Devices) When tested with Ag ions at an LET = 64.8 MeV/mg/cm2, VIN = 14.7 V, TC = 85˚C, the ISL7457SRH was found to be vulnerable to SEL/SEB. When tested with Ag ions at an LET = 64.8 MeV/mg/cm2, VIN = 14V, TC = 85˚C, the ISL7457SRH was found to be vulnerable to SEL/SEB. When tested with Ag ions at an LET = 86.4 MeV/mg/cm2, VIN = 6.1V, TC = 125˚C, the ISL7457SRH was found to be immune to SEL/SEB. SET behavior consisted of numerous low-high-low transients at the outputs of the C and D drivers that lasted for < 500ns. The capture cross section was computed to be 8.88 x 10-5 cm2. Appendix Figures 2 - 6 that follow show representative oscilloscope waveforms captured during the SEE testing. 5 Figure 2: Short duration (< 500 ns) low-high-low transients on OUTC and OUTD (Au Ions, LET = 85.4 MeV/mg/cm2, VIN = 15 V, TC = 25°C, Ax = VD1, Bx = OUTB, Cx = OUTC, Dx= OUTD) Figure 3: Long Duration (> 18 us) high-low transient on OUTA (Au ions, LET = 85.4 MeV/mg/cm2, VIN = 15 V, TC = 25°C, Ax = VD1, Bx = OUTA, Cx = OUTB, Dx = OUTC) 6 Figure 4: Long Duration (> 18 us) high-low transient on OUTB (Au ions, LET = 85.4 MeV/mg/cm2, VIN = 15 V, TC = 25°C, Ax = VD1, Bx = OUTA, Cx = OUTB, Dx = OUTC) Figure 5: Short duration (< 500 ns) low-high-low transients on OUTC and OUTD (Ag ions, LET = 42.2 MeV/mg/cm2, VIN = 15 V, TC = 25°C, Ax = VD1, Bx = OUTB, Cx = OUTC, Dx= OUTD) 7 Time in µs Figure 6: Short duration (< 500 ns) low-high-low transients on OUTC and OUTD (Ag ions, LET = 86.4 MeV/mg/cm2, VIN = 6.1 V, TC = 125°C) 8