A LOW-VOLTAGE LOW-POWER WIDE-RANGE CMOS VARIABLE GAIN AMPLIFIER

In this paper, a compact low-power (LP) low-voltage (LV) metal-oxide-s emiconductor only (MOS-only) variable gain amplifier (VGA) is introduc ed. This amplifier based on complementary MOS (CMOS) transistors opera ting in strong inversion is composed of a pseudo-exponential current-t o-voltage converter, analog multiplier, and output stage. The gain of the amplifier is controlled exponentially by a novel wide-range pseudo -exponential current-to-voltage converter implemented with two back-to -back connected current mirrors exhibiting superb exponential characte ristic. Also, a new LV/LP composite transistor is introduced to increa se the input dynamic range of the multiplier. The amplifier is fabrica ted using a 2-mu m MOSIS n-well process, and its simulation and measur ement results are shown in detail.