INTRODUCTION

The S1M8821/22/23 is a high performance dual frequency synthesizer with integrated prescalers designed for RF operation up to 1.2GHz/2.0GHz/2.5GHz and IF operation up to 520MHz. The S1M8821/22/23 contains dual-modulus prescalers. The RF synthesizer adopts a 64/65 or a 128/129 prescaler(32/33 or 64/65 for the S1M8823) and the IF synthesizer adopts an 8/9 or a 16/17 prescaler.

FEATURES

• High operating frequency dual synthesizer

— S1M8821 : 0.1 to 1.2GHz (RF)/ 45 to 520MHz (IF)

— S1M8822 : 0.2 to 2.0GHz (RF)/ 45 to 520MHz (IF)

— S1M8823 : 0.5 to 2.5GHz (RF)/ 45 to 520MHz (IF)

• Very low current consumption(8821:3.5mA, 22:4.5mA, 23:5.5mA)

• Operating voltage range : 2.7 to 4.0V

• Selectable power saving mode(Icc=1uA typical @3V)

• Dual modulus prescaler : S1M8821/22 (RF) 64/65 or 128/129 S1M8823 (RF) 32/33 or 64/65 S1M8821/22/23 (IF) 8/9 or 16/17

• Programmability via serial bus interface

• No dead-zone PFD

• Variable charge pump output current

• High speed lock mode

APPLICATIONS

• Cellular telephone systems : S1M8821

• Portable wireless communications : S1M8822 (PCS/PCN, cordless)

• Wireless Local Area Networks (W-LANs) : S1M8823

• Other wireless communication systems