Programmable gain amplifier for 13.56 MHz radio receiver in CMOS 90 nm technology

In this paper, a PGA (Programmable Gain Amplifier) for 13.56 MHz radio receivers will be presented. The gain of the simulated PGA, based on the circuit presented in [1], is controlled by 4-bit digital word and is linear in decibels using apseudo-exponential function. The circuit achieves a gain range of 22.91 dB (0.53-23.44 dB) with an absolute gain error not higher than 0.74 dB. The maximum gain step and minimum 3 dB bandwidth are equal to 2.02 dB and 125.8 MHz, respectively. The amplifier consumes 1.52 mW in active and 1.50 nW in standby mode from 2.5 V single power supply.