LMX2305 Datasheet | National Semiconductor

Description The LMX2305 is a high performance frequency synthesizer with an integrated prescaler designed for RF operation up to 550 MHz It is fabricated using National’s ABi C IV Bi CMOS process The LMX2305 contains a dual modulus prescaler which can select either a 64 65 or a 128 129 divide ratio at input frequencies of up to 550 MHz LMX2305 which employs the digital phase lock loop technique bined with a high quality reference oscillator and a loop filter provides the tuning voltage for the voltage controlled oscillator to generate a very stable low noise local oscillator signal Serial data is transferred into the LMX2305 via a three line MICROWIRETM interface (Data Enable Clock) Supply voltage can range from 2 65V to 5 5V The LMX2305 features very low current consumption typically 4 0 m A at 2 75V The LMX2305 is available in a TSSOP 20-pin surface mount plastic package Features RF operation up to 550 MHz 2 65V to 5 5V operation Low current consumption ICC e 4 0 m A (typ) at VCC e 2 75V Dual modulus prescaler 64 65 or 128 129 Internal balanced low leakage charge pump Small-outline plastic surface mount TSSOP 0 173 wide package Applications Analog Cellular telephone systems (AMPS ETACS NMT) Portable wireless munications (PCS PCN cordless) Wireless local area networks (WLANs) Other wireless munication systems Pagers Block Diagram TL W 12459 - 1 TRI-STATE is a registered trademark of National Semiconductor Corporation MICROWIRETM and PLLatinum TM are trademarks of National Semiconductor Corporation C1996 National Semiconductor Corporation TL W 12459 RRD-B30M126 Printed in U S A http national Connection Diagram TL W 12459 - 2 20-Lead (0 173 Wide) Thin Shrink Small Outline Package (TM) Order Number LMX2305TM or LMX2305TMX See NS Package Number MTC20 Pin Descriptions Pin No 1 Pin Name OSCIN I O I Description Oscillator input A CMOS inverting gate input intended for connection to a crystal resonator for operation as an...