A 0.25 μm CMOS transceiver front-end for GSM

To meet GSM standards, critical building blocks in the RF front-end must provide low noise figures, high linearity and predictable gain, while requiring as few external passive components and consume as little current as possible. This paper presents a transceiver front-end in 0.25 μm CMOS, that includes an 18 mA LNA with 2 dB NF and -2.8 dBm output CP, a 6 mA mixer with 12.6 dB (SSB) NF and 9 dBm IP3, a 71 MHz IF amplifier with programmable gain between -20 to 60 dB in 2 dB steps. Consuming only 2.5 mA, the differential accuracy of the gain steps is within 0.3 dB, which enables the AGC amp to double as a received signal strength indicator. The transmitter pre-amplifier has 21 dB gain, an output CP of 5.8 dBm, requires no output filter and consumes 29 mA