Low-voltage CMOS programmable gain amplifier for UHF applications

A CMOS programmable gain amplifier suitable for low-voltage operation over the very high frequency range is presented. The scheme is based on a very simple common-mode feedforward pseudo-differential pair with resistive loads. Post-layout results for a 1.8 V-0.18 mum CMOS design show a linear-in-dB programmable gain from 0 to 12 dB with a -3 dB bandwidth above 1.4 GHz and power consumption below 17 mW over all the gain range.