The HD155111F was developed for PCN (DCS1800) cellular systems, and integrates most of the functions of a transceiver. The HD155111F incorporates the bias circuit for a RF LNA, a 1st mixer, 1st-IF amplifier, 2nd mixer, AGC amplifier and an IQ quadrature demodulator for the receiver, and an IQ quadrature modulator and offset PLL for the transmitter. Also, on chip are the dividers for the 1st & 2nd local oscillator signals and 90 phase splitter. Moreover the HD155111F includes control circuits to implement power saving modes. These functions can operate down to 2.7 V and are housed in a 48-pin LQFP SMD package.