Description
The HD155121F is a RF transceiver IC for GSM and PCN dual band cellular systems, and integrates most of the low power silicon functions of a transceiver. The HD155121F incorporates two bias circuits for RF LNAs, two first mixers, a second mixer, a programmable gain amplifier, and an IQ demodulator for the receiver, and an IQ modulator and offset PLL for the transmitter. Also, on chip are dividers for the phase splitter. Moreover the HD155121F 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.

FEATUREs
• Highly integrated RF processing for hand-portables
• Operating supply voltage
   ― VCC : 2.7 to 3.6 V
   ― Phase comparator and TXVCO driver circuit : 2.7 to 5.25 V
• Current consumption
   ― Rx mode (GSM) : 53 mA + LNA current
   ― Rx mode (PCN) : 52 mA + LNA current
   ― Tx mode (GSM) : 36 mA
   ― Tx mode (PCN) : 37 mA
   ― Idle mode :1 µA
• Operating temperature : –20 to +75 degree
• LQFP 48pin SMD (Low Profile Quad Flat Package)
• Wide operating frequencies
   ― Rx RF GSM : 925 - 960 MHz
                   PCN : 1805 - 1880 MHz
             1st IF : 225 MHz
             2nd IF : 45 MHz
   ― Tx RF GSM : 880 - 915 MHz
                   PCN : 1710 - 1785 MHz
        IF GSM : 270 MHz
             PCN : 135 MHz
• Offset PLL architecture for Transmitter
• High dynamic range Programmable Gain Amplifier (PGA)