Variable gain amplifiers based on a new approximation method to realize the exponential function

K.M. Abdelfattah1, A.M. Soliman2
1Electrical Engineering Department, University of California, Los Angeles, CA, USA
2Electronics and Electrical Communication Department, Giza, Egypt

Tóm tắt

A new current mode variable-gain amplifier (VGA) is developed. The new circuit is based on a novel approximation function that is very close to the ideal exponential relation over a very wide range. Pspice simulations are provided based on Mietec 0.5-/spl mu/m CMOS technology. The simulations show that the dynamic range achieved is over 50 dB in a single stage. The proposed circuit consumes average power less than 1.2 mW using /spl plusmn/1.5 V supply voltages.

Từ khóa

#Approximation methods #Dynamic range #CMOS technology #Circuit simulation #Difference equations #Voltage #Gain control #Auditory system #Communication system control #Bipolar transistors

Tài liệu tham khảo

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