LMX2305

LMX2305 PLLatinum 550 MHz Frequency Synthesizer for RF Personal Communications PRELIMINARY August 1996 LMX2305 PLLatinum TM 550 MHz Frequency Synthesizer for RF Personal Communications General 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 ABiC IV BiCMOS 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 combined 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 mA at 2 75V The LMX2305 is available in a TSSOP 20-pin surface mount plastic package Features Y Y Y Y Y Y RF operation up to 550 MHz 2 65V to 5 5V operation Low current consumption ICC e 4 0 mA (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 Y Y Y Y Y Analog Cellular telephone systems (AMPS ETACS NMT) Portable wireless communications (PCS PCN cordless) Wireless local...