A high-speed logarithmic amplifier

Reports on the improvement of frequency responses of a logarithmic amplifier with a Paterson transdiode connection. The improvement of the response speed has been achieved by using a phase compensation technique. Small- signal response analysis of the logging circuit revealed the effects of a series resistor
R
_P
and a parallel capacitor
C
_P
on the response of the circuit. The improvement of the frequency characteristics is remarkable at high current levels. These facts were proved by the practical logarithmic amplifier.