LMX1600/LMX1601/LMX1602

LMX1600

2.0 GHz/500 MHz

LMX1601

1.1 GHz/500 MHz

LMX1602

1.1 GHz/1.1 GHz

General Description

The LMX1600/01/02 is part of a family of monolithic inte-

grated dual frequency synthesizers designed to be used in a

local oscillator subsystem for a radio transceiver. It is fabri-

cated using National’s 0.5u ABiC V silicon BiCMOS process.

The LMX1600/01/02 contains two dual modulus prescalers,

four programmable counters, two phase detectors and two

selectable gain charge pumps necessary to provide the con-

trol voltage for two external loop filters and VCO loops. Digi-

tal filtered lock detects for both PLLs are included. Data is

serial interface (Data, Clock, LE).

V

CC

supply voltage can range from 2.7V to 3.6V. The

LMX1600/01/02 features very low current consumption -

typically 4.0 mA at 3V for LMX1601, 5.0 mA at 3V for

LMX1600 or LMX1602. Powerdown for the PLL is hardware

controlled.

The LMX1600/01/02 is available in a 16 pin TSSOP surface

mount plastic package.

Features

n

V

n

Low current consumption:

n

PLL Powerdown mode: I

n

Dual modulus prescaler:

— 2 GHz/500 MHz option:

(Main) 32/33 (Aux) 8/9

— 1.1 GHz/500 MHz option:

(Main) 16/17 (Aux) 8/9

— 1.1 GHz/1.1 GHz option:

(Main) 16/17 (Aux) 16/17

n

Digital Filtered Lock Detects

Applications

n

Cordless / Cellular / PCS phones

n

Other digital mobile phones

Functional Block Diagram

DS100129-1

PRELIMINARY

March 1998

© 1998 National Semiconductor Corporation

DS100129

www.national.com