Accession Number : AD0476993


Title :   DESIGN FOR A HIGH-DUTY-CYCLE, BIPOLAR, LOGARITHMIC VIDEO AMPLIFIER.


Descriptive Note : Technical rept.,


Corporate Author : STANFORD UNIV CA STANFORD ELECTRONICS LABS


Personal Author(s) : McMaster, R L


Report Date : Oct 1965


Pagination or Media Count : 50


Abstract : The theoretical and practical aspects of a high-duty-cycle, bipolar, logarithmic, video pulse amplifier are described. The approximations to a logarithmic transfer function are reviewed. The realization of a logarithmic transfer function is accomplished by a cascade of transistorized feedback-pair stages utilizing feedback elements with exponential voltage-current characteristics. Both diode and transistor transconductance feedback are described. Practical bipolar and unipolar amplifier designs are presented. Both amplifiers have a duty-cycle capability of at least 15 percent and a video dynamic range of 100 db. The deviation from a logarithmic response is less than plus or minus 0.5 db and the noise figure is 11 db. The rise time for a small-signal pulse is 0.2 microsecond and that for a large-signal pulse is 0.05 microsecond. (Author)


Descriptors :   *PULSE AMPLIFIERS , *TRANSISTOR AMPLIFIERS , *VIDEO AMPLIFIERS , *LOGARITHMIC AMPLIFIERS , FUNCTIONS(MATHEMATICS) , FEEDBACK AMPLIFIERS , SEMICONDUCTOR DIODES , CASCADE STRUCTURES , VOLTAGE , ELECTRICAL RESISTANCE , BROADBAND , COMPARATORS , CRYSTAL DETECTORS , TEMPERATURE , ELECTRICAL IMPEDANCE , GAIN , ENGINEERING DRAWINGS


Subject Categories : Electrical and Electronic Equipment


Distribution Statement : APPROVED FOR PUBLIC RELEASE