LMX2330A/LMX2331A/LMX2332A
PLLatinum™ Dual Frequency Synthesizer for RF
Personal Communications
LMX2330A
LMX2331A
LMX2332A
2.5 GHz/510 MHz
2.0 GHz/510 MHz
1.2 GHz/510 MHz
General Description
The LMX233xA family of monolithic, integrated dual frequency synthesizers, including prescalers, is to be used as a
local oscillator for RF and first IF of a dual conversion transceiver. It is fabricated using National’s ABiC IV silicon
BiCMOS process.
The LMX233xA contains dual modulus prescalers. A 64/65
or a 128/129 prescaler (32/33 or 64/65 in the 2.5 GHz
LMX2330A) can be selected for the RF synthesizer and a
8/9 or a 16/17 prescaler can be selected for the IF synthesizer. LMX233XA, which employs a digital phase locked loop
technique, combined with a high quality reference oscillator
and loop filters, provides the tuning voltages for voltage controlled oscillators to generate very stable low noise RF and
IF local oscillator signals. Serial data is transferred into the
LMX233xA via a three wire interface (Data, Enable, Clock).
Supply voltage can range from 2.7V to 5.5V. The LMX233xA
family
features
very
low
current
consumption;
LMX2330A — 13 mA at 3V, LMX2331A — 12 mA at 3V,
LMX2332A — 8 mA at 3V.
The LMX233xA are available in a TSSOP 20-pin surface
mount plastic package.
Features
2.7V to 5.5V operation
Low current consumption
Selectable powerdown mode: ICC = 1 µA typical at 3V
Dual modulus prescaler:
LMX2330A (RF) 32/33 or 64/65
LMX2331A/32A (RF) 64/65 or 128/129
LMX2330A/31A/32A (IF) 8/9 or 16/17
n Selectable charge pump TRI-STATE ® mode
n Selectable FastLock™ mode
n Small outline, plastic, surface mount TSSOP 0.173"
wide package
n
n
n
n
Applications
n
n
n
n
n
Portable Wireless Communications (PCS/PCN, cordless)
Cordless and cellular telephone systems
Wireless Local Area Networks (WLANs)
Cable TV tuners (CATV)
Other wireless communication systems
Functional Block Diagram
DS012331-1
TRI-STATE ® is a registered trademark of National Semiconductor Corporation.
Fastlock™, MICROWIRE™ and PLLatinum™ are trademarks of National Semiconductor Corporation.
© 1999 National Semiconductor Corporation
DS012331
www.national.com
LMX2330A/LMX2331A/LMX2332A PLLatinum Dual Frequency Synthesizer for RF Personal
Communications
May 1999
