LMX2515
PLLatinum
™
Frequency Synthesizer System
with Integrated VCO
General Description
LMX2515 is a highly integrated, high performance, low
power frequency synthesizer system optimized for Japan
PDC mobile handsets. Using a proprietary digital phase
locked loop technique, LMX2515 generates very stable, low
noise local oscillator signals for up and down conversion in
wireless communications devices.
LMX2515 includes a voltage controlled oscillator (VCO), a
loop filter, and a fractional-N RF PLL based on a delta sigma
modulator. In concert these blocks form a closed loop RF
synthesizer system. The LMX2515LQ0701 supports the Ja-
pan PDC800 band and the LMX2515LQ1321 supports Ja-
pan PDC1500 band.
Serial data is transferred to the device via a three-wire
MICROWIRE interface (DATA, LE, CLK).
Operating supply voltage ranges from 2.5 V to 3.3 V.
LMX2515 features low current consumption.
LMX2515 is available in a 28-pin leadless leadframe pack-
age (LLP).
Features
n Small size
5.0 mm X 5.0 mm X 0.75 mm 28-Pin LLP Package
n RF Synthesizer System
Integrated RF VCO
Integrated Loop Filter
Low Spurious, Low Phase Noise Fractional-N RF PLL
Based on 10-Bit Delta Sigma Modulator
Frequency Resolution Down to 20 kHz
n Supports Various Reference Frequencies
12.6/14.4/25.2/26.0 MHz
n Fast Lock Time: 300 µs
n Low Current Consumption
n 2.5 V to 3.3 V operation
n Digital Filtered Lock Detect Output
n Hardware and Software Power Down Control
Applications
n Japan PDC systems at 800 MHz frequency band.
n Japan PDC systems at 1500 MHz frequency band.
Functional Block Diagram
20068807
FastLock
™
is a trademark of National Semiconductor Corporation.
TRI-STATE
®
is a registered trademark of National Semiconductor Corporation.
PLLatinum
™
is a trademark of National Semiconductor Corporation.
April 2004
LMX2515 PLLatinum Frequency Synthesizer System with Integrated VCO
© 2004 National Semiconductor Corporation DS200688 www.national.com
