Monolithically integrated high performance digital variable gain amplifiers

In this paper, a new monolithically integrated, digitally-controlled variable gain amplifier (DVGA) is presented. The DVGA includes a gain block, a digital step attenuator (DSA), and a ¼ W driver amplifier, fabricated by using commercial GaAs BiFET process. This high performance, low cost DVGA operates from 100MHz to 4000MHz, with 0.5dB step and 31.5dB gain dynamic range. It shows the noise figure of 4dB, output IP3 of 41dBm, and 25dBm output power at 1dB gain compression (P1dB). The DVGA consumes total 175mA DC current with 5V power supply at room temperature.