A wideband varactor-tuned BICMOS Negative Inductance design

Abstract

This paper describes the design of a wideband varactor-tuned BiCMOS Negative Inductance, with NXP semiconductors 0.25 μm BiCMOS SiGe process. The structure consists in a loop with a C-gyrator associated with an amplifier. This amplifier allows both inverting the impedance behaviour and obtaining a negative inductance. Furthermore, differential stages are used to benefit the floating effect to achieve a floating inductance. In these conditions, the capacitive effect is inverted and a Negative Impedance Converter is realized. For our application, the targeted value is -20 nH with a frequency range from 200 to 900 MHz. Firstly, this architecture has been presented in [1] by White and al. but in this paper we use a varactor which allows adjusting the negative value. At 2.7 V power supply voltage, a power of only 11 mW is dissipated.