LMX2305 Datasheet, PDF (1/14 Pages) National Semiconductor (TI) – PLLatinumTM 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 fre-
quencies 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 gener-
ate a very stable low noise local oscillator signal
Serial data is transferred into the LMX2305 via a three line
MICROWIRE^TM interface (Data Enable Clock) Supply volt-
age 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 _{RF operation up to 550 MHz}
Y _{2 65V to 5 5V operation}
Y _{Low current consumption}
I_CC e 4 0 mA (typ) at V_CC e 2 75V
Y _{Dual modulus prescaler 64 65 or 128 129}
Y _{Internal balanced low leakage charge pump}
Y _{Small-outline plastic surface mount TSSOP}
0 173 wide package
Applications
Y _{Analog Cellular telephone systems}
(AMPS ETACS NMT)
Y _{Portable wireless communications}
(PCS PCN cordless)
Y _{Wireless local area networks (WLANs)}
Y _{Other wireless communication systems}
Y _Pagers
Block Diagram
TL W 12459 – 1
TRI-STATE is a registered trademark of National Semiconductor Corporation
MICROWIRETM and PLLatinumTM are trademarks of National Semiconductor Corporation
C1996 National Semiconductor Corporation TL W 12459
RRD-B30M126 Printed in U S A
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