Accession Number : ADA141369

Title :   Basic EMC (Electromagnetic Compatibility) Technology Advancement for C3 Systems. Volume 1. A Nonlinear Macromodel of the Bipolar Integrated Circuit Operational Amplifier for Electromagnetic Interference Analysis.

Descriptive Note : Final technical rept. Jun 81-Jun 82,


Personal Author(s) : Chen,G K C ; Whalen,J J

PDF Url : ADA141369

Report Date : Dec 1983

Pagination or Media Count : 137

Abstract : A macromodel containing two transistors can accurately predict how amplitude modulated RF signals with RF carrier frequencies in the 0.05 to 100.0 MHz range are demodulated in bipolar operational amplifiers (micro A741 and LM10 op amps) to cause undesired low frequency responses related to the modulation envelope of the RF signals. The original op amp macromodel which was developed by Boyle at al was modified by adding four capacitors C(sub) to account for parasitic capacitance effects in integrated circuit op amps. A procedure for assigning C(sub) values is given. The macromodel can be used when the RFI signals are incident upon the op amp input terminals. The use of the macromodel leads to a substantial reduction in computer time and expense. The ability of the nonlinear macromodel to represent the overall integrated circuit nonlinear response with only two transistors at the input stage is explained using the feedback theory of cascaded nonlinear transfer functions. In an operational amplifier with a linear feedback in its second stage, the nonlinear response of the second stage is suppressed. The overall nonlinear response is dominated by the nonlinearities of the input stage. (Author)

Descriptors :   *Operational amplifiers, *Electromagnetic compatibility, *Bipolar transistors, *Command and control systems, *Integrated circuits, *Communication equipment, Transmission lines, Circuit analysis, Coupling(Interaction), Electric cables, Equivalent circuits, Electromagnetic radiation, Electromagnetic fields, Digital computers, Near field, Measurement, Signals, Amplitude modulation, Theory, Linear systems, Comparison, Methodology, Nonlinear systems, Fortran, Frequency response, Parameters, Selection

Subject Categories : Electrical and Electronic Equipment
      Computer Programming and Software
      Computer Hardware
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE