An RF variable gain amplifier with linear-in-dB gain steps and automatic power consumption optimization

Abstract

This paper describes a novel power optimized RF amplifier with linear in dB gain steps. Using basic P-N junction diode in 45nm CMOS process the implemented VGA provides large dynamic range with accurate linear-in-dB gain steps. The gain steps of the VGA do not depend on process variation and has a predictable variation across temperature. The VGA also has an automatic power reduction mechanism which reduces power consumption at low VGA gain.