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Lee, C. I.

Publications and source records attributed to Lee, C. I..

12 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1997

Total Ionizing Dose Effects on 64Mb 3.3V DRAMs

64Mb 3.3V CMOS DRAMs from two different manufacturers were tested for total dose. Retention time, power supply current, and functionality were used to characterize device response.

Ionizing Dose Effects Samsung Mitsubishi↗
NASA NTRS1997

Degradation of Precision Reference Devices in Space Environments

This paper presents radiation test results for several different precision voltage devices. Their degradation is compared to that expected for the basic bandgap reference circuit, which is used as a theoretical benchmark, and uses only npn transistorss.

Precision↗
NASA NTRS1996

Total Dose Effects and Hardness Assurance for Optocouplers

The operation and efficiency of optocouplers depend on a number of different factors, and the way that these factors are degraded by radiation must be properly understood in order to apply these devices in space systems.

optocouplers optocoupler efficiency LED degradatio↗
NASA NTRS1996

Hardness Assurance Techniques for New Generation COTS Devices

Hardness Assurance (HA) techniques and total dose radiation characterization data for new generation linear and COTS devices from various manufacturers are presented. A bipolar op amp showed significant degradation at HDR, not at low dose rate environment. New generation low-power op amps showed more degradation at low voltage applications. HA test techniques for COTS devices are presented in this paper.

New Millenium advanced technologies miniature spac↗
NASA NTRS1995

Hardness Assurance and Testing Techniques for High Resolution (12- to 16-bit) Analog-to-Digital Converters

Discussed are hardness assurance and testing techniques to test and evaluate total dose radiation degradation of high resolution A/D converters. Because high-speed, high-resolution converters are critical parts in a digital signal processing or data acquisition system, the evaluation of performance in the early design phase is very important. Converters from three manufacturers are evaluated.

Analog-to-Digital↗
NASA NTRS1994

Total Ionizing Dose Effects on High Resolution (12-/14-bit) Analog-to-Digital Converters

This paper reports total dose radiation test results for high resolution 12-/14-bit A/D converters. Small changes in internal components can cause these devices to fail their specifications at relatively low total dose levels. Degradation of signal-to-noise ratio becomes increasingly importamt for high accuracy converters. Rebound effects in the thick-oxide MOS devices causes these responses to be different at low and high dose rates, which is a major concern for space applications.

radiation ionizing analog-to-digital converters MO↗
NASA NTRS1993

Total Ionizing Dose Effects in 12-Bit Successive-Approximation Analog-To-Digital Converters

Analog-to-digital (A/D) converters are critical components in many space and military systems, and there have been numerous advances in A/D converter technology that have increased the resolution and conversion time. The increased performance is due to two factors: (1) advances in circuit design and complexity, which have increased the number of components and the integration density; and (2) new process technologies, such as BiCMOS, which provide better performance, cost, and smaller size in mixed-signal circuits. High-speed A/D converters, with conversion rates above 1 MHz, present a challenge to circuit designers and test engineers. Their complex architectures and high-performance specifications result in numerous possible failure modes when they are subjected to ionizing radiation. The dominant failure mode may depend on the specific application because the fundamental effects on MOS and bipolar transistors are strongly affected by bias conditions.

Lee, C. I.↗