J.W. Howard

Role of heavy-ion nuclear reactions in determining on-orbit single event error rates

Simulations show that neglecting ion-ion interaction processes (both particles having Z>1) results in an underestimation of the total on-orbit single event upset error rate by more than two orders of magnitude for certain technologies. The inclusion of ion-ion nuclear reactions leads to dramatically different SEU error rates for CMOS devices containing high Z materials compared with direct ionization by the primary ion alone. Device geometry and material composition have a dramatic effect on charge deposition in small sensitive volumes for the spectrum of ion energies found in space, compared with the limited range of energies typical of ground tests.

Effect of amplifier parameters on single-event transients in an inverting operational amplifier

Laser data and simulation tools are combined to investigate the single-event transient response of the LM124 operational amplifier. The effect of the bandwidth and gain on transients originating in different stages in the operational amplifier is studied. We found that the single-event transient response of the LM124 operational amplifier in an inverting configuration was dependent on the bandwidth of the amplifier, the gain, and on the values of the resistors used to program the gain of the amplifier. We show the results of simulations which illustrate how these changes impact the single-event transient response of the amplifier. An analysis of the results suggests which properties of an operational amplifier will provide a better single-event transient response.

Circuit modeling of the LM124 operational amplifier for analog single-event transient analysis

This work presents the development of a transistor-level circuit model of the LM124 operational amplifier specifically engineered and calibrated for analog single-event transient (ASET) computer simulations. The techniques presented rely heavily on datasheet specifications for electrical parameterization and experimental laser probing for dc and transient calibration. The resulting circuit model proves to be suitable for broad-beam SET predictions and fault diagnostics for space applications.

An Analysis of Single Event Upset Dependencies on High Frequency and Architectural Implementations within Actel RTAX-S Family Field Programmable Gate Arrays

In order to investigate frequency and architectural effects on Single Event Upset cross sections within RTAX-S FPGA devices, a novel approach to high speed testing is implemented. Testing was performed at variable speeds ranging from 15 MHz to 150 MHz

Recent radiation damage and single event effect results for candidate spacecraft electronics

We present data on the vulnerability of a variety of candidate spacecraft electronics to proton and heavy ion induced single event effects and proton-induced damage. Devices tested include optoelectronics, digital, analog, linear bipolar, hybrid devices, Analog-to-Digital Converters (ADCs), Digital-to-Analog Converters (DACs), and DC-DC converters, among others.

Recent radiation damage and single event effect results for microelectronics

We present heavy ion and proton single event effects (SEE) as well as radiation damage ground test results for candidate spacecraft electronics. Microelectronics tested include digital, analog, and hybrid devices.

Total dose and single event effects testing of the Intel pentium III (P3) and AMD K7 microprocessors

To understand the radiation sensitivity and radiation response, Intel Pentium III and AMD K7 microprocessors were tested for total ionizing dose and single event effects. The processors have been found to be extremely tolerant to total ionizing dose and no radiation-induced latchups have been observed with protons or heavy ions to an LET of approximately 15 MeV-cm/sup 2//mg. Single event upset and functional interrupts have been observed for both protons and heavy ions.

Prediction of early lethal SEGR failures of VDMOSFETs for commercial space systems

Quantitative risk assessments are presented for two radiation-hardened MOSFETs (Harris FSL11A0 and FRL11A0) using an extracted expression, integral flux curves representing different conditions, and experimentally-determined signature curves taken at different ion impact angles. The effectiveness of certain parameters including the selected orbit, spacecraft shielding thickness, drain and gate biases, device hardness, and time of exposure are discussed. Failures are studied using normalized Monte Carlo simulations validated by statistical methods. These validated Monte Carlo simulations are then used to extract and present an extracted expression. The concept of a lethal ion rate is discussed. Single event gate rupture (SEGR) failure thresholds at different ion impact angles are measured and reported on the Harris FSL11A0 and FRL11A0 (radiation-hardened vertical MOSFETs having similar layouts but with different SEGR sensitivities). Integral flux curves are presented for various orbits and conditions. Predictions of very early failures are performed using the extracted expression, the integral flux curves, and the new signature curves. Based upon these predictions, the influence of selected parameters are evaluated.

Current single event effects results for candidate spacecraft electronics for NASA

We present data on the vulnerability of a variety of candidate spacecraft electronics to proton and heavy ion induced single event effects. Devices tested include digital, analog, linear bipolar, and hybrid devices, among others.

Single event effects testing of the Linfinity SG1525A pulse width modulator controller

The Linfinity SG1525A pulse width modulator controller was investigated for single event effects. No latchup events were observed but pulse dropouts and multiple consecutive pulses were observed. Additionally, experimental data collection methodology led to erroneous temporal overlap events being observed. The methodology and care needed to avoid these effects are discussed.