The AD6459 is a 3 V, low power receiver IF subsystem for operation at input frequencies as high as 500 MHz and IFs from 5 MHz up to 50 MHz. It is optimized for operation in GSM, DCS1800 and PCS1900 receivers. It consists of a mixer, an IF amplifier, I and Q demodulators, a phase-locked quadrature oscillator, a precise AGC subsystem, and a biasing system with external power-down.