CMOS current-mode exponential-control variable-gain amplifier - Electronics Letters
نویسندگان
چکیده
the output on the amplitude of the input in a series of simulations, which showed that the peak and the plateau values of the response are nonlinear monotonic increasing functions of J and nonlinear monotonic decreasing functions of I. Together, these results suggest that the circuit encodes the contrast rather than the absolute amplitude of the input. Fig. 3 shows that the peak and the plateau values of the response are approximately linear functions of Weber contrast on a logarithmic scale. Fig. 4 shows that the peak and the plateau values of the response are approximately linear functions of Michelson contrast on a linear scale, in particular when contrast is above 0.3.
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