Low-Power Decibel-Linear Programmable-Gain Amplifier With Complementary Current-Switching Technique

In this study, a low-power decibel-linear (dB-linear) programmable-gain amplifier (PGA) is proposed. Based on the complementary current-switching technique, the proposed PGA achieves a wider bandwidth, a large gain control range, and a low dB-linear error while reducing the DC power consumption compared with the conventional PGA. To verify this, the proposed PGA was implemented using a 65-nm CMOS process. It provides a dB-linear gain control range of 59.7 dB with 1-dB steps while achieving a dB-linear gain error of less than 0.29 dB. Under a 1-V supply voltage, the proposed PGA delivers a peak gain of 34.9 dB and a 3-dB bandwidth of 270 MHz, consuming only 0.6 mW DC power.