Accession Number:

ADA278644

Title:

Rapid and Accurate Timing Simulation of Radiation-Hardened Digital Microelectronics Using VHDL

Descriptive Note:

Master's thesis

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING

Personal Author(s):

• Brothers, JR, Charles P.

Report Date:

1994-03-01

Pagination or Media Count:

164.0

Abstract:

This dissertation presents the development of a fast, accurate, timing simulation capability based on VHSIC Hardware Description Language VHDL without the use of back annotation of timing delay information. This VHDL-based timing simulator is intended for use with radiation-hardened microelectronics in simulating timing of circuit operation in pre-radiation, post-radiation 1 MradSi total dose, and ionizing dose radiation environments. Development of the timing models are presented. The implementation of the timing models are incorporated into a VHDL library composed of basic logic gates and flip-flops. Simulations of complex circuits were run in SPICE and VHDL to assess the timing accuracy and simulation run time of the VHDL-based timing simulator versus SPICE. Results of the simulations are presented. Final evaluation of the simulator included testing of a microprocessor control unit. In all cases, the VHDL-based simulation ran over two orders of magnitude faster than the equivalent SPICE simulation. In the pre- and post-radiation environment, accuracy estimates are usually within five percent and never exceed 12 percent. Worst-case timing estimate errors increase above 15 percent for dose rates above 1.Ox1Oexp 11 radsSi per second. This VHDL-based timing simulator represents an improvement over SPICE in the ability to quickly simulate complex circuits. CMOS Logic simulation, Logic circuit simulation, Radiation-hardened microelectronics, Transient radiation effects, VHDL.

Descriptors:

• *COMPUTERIZED SIMULATION
• *MICROELECTRONICS
• *RADIATION HARDENING
• COMPUTER PROGRAMS
• SIMULATORS
• SIMULATION
• TRANSIENTS
• RADIATION
• MODELS
• MICROPROCESSORS
• HIGH VELOCITY
• RADIATION DOSAGE
• NEUTRONS
• IONIZING RADIATION
• COMPLEMENTARY METAL OXIDE SEMICONDUCTORS
• DOSE RATE
• CIRCUITS
• LOGIC CIRCUITS
• DELAY
• OPERATION
• TRANSIENT RADIATION EFFECTS
• RADIATION EFFECTS
• RATES
• THESES
• INTEGRATED CIRCUITS
• FIELD EFFECT TRANSISTORS
• TIME
• SILICON
• ERRORS

Subject Categories:

• Electromagnetic Shielding
• Computer Programming and Software

Distribution Statement:

APPROVED FOR PUBLIC RELEASE