NSC LMX2324SLBX Datasheet

LMX2324
PLLatinum

™

2.0 GHz Frequency Synthesizer for RF

Personal Communications

General Description

The LMX2324 is a high performance frequency synthesizer
with integrated 32/33 dual modulus prescaler designed for
RF operation up to 2.0 GHz. Using a proprietary digital
phase locked loop technique, the LMX2324’s linear phase
detector characteristics can generate very stable, low noise
control signals for UHF and VHF voltage controlled oscilla­tors.

Serial data is transferred into the LMX2324 via a three-line
MICROWIRE

™

interface (Data, LE, Clock). Supply voltage
range is from 2.7V to 5.5V. The LMX2324 features very low
current consumption, typically 3.5 mA at 3V. The charge
pump provides 4 mA output current.

The LMX2324 is manufactured using National’s ABiC V
BiCMOS process and is packaged in a 16-pin TSSOP and a
16-pin Chip Scale Package (CSP).

Features

n RF operation up to 2.0 GHz
n 2.7V to 5.5V operation
n Low current consumption: I

CC

= 3.5 mA (typ) at VCC=

3.0V

n Dual modulus prescaler: 32/33
n Internal balanced, low leakage charge pump

Applications

n Cellular telephone systems (GSM, NADC, CDMA, PDC)
n Personal wireless communications (DCS-1800, DECT,

CT-1+)

n Wireless local area networks (WLANs)
n Other wireless communication systems

Functional Block Diagram

TRI-STATE®is a registered trademark of National SemiconductorCorporation.
MICROWIRE

™

and PLLatinum™are trademarks of National Semiconductor Corporation.

DS101030-1

PRELIMINARY

November 1999

LMX2324 PLLatinum 2.0 GHz Frequency Synthesizer for RF Personal Communications

© 1999 National Semiconductor Corporation DS101030 www.national.com

Connection Diagrams

Pin Descriptions

Pin No.

Pin

Name

I/O Description

TSSOP16 CSP16

21V

P

— Power supply for charge pump. Must be ≥ V

CC

32CP

o

O Internal charge pump output. For connection to a loop filter for driving the

voltage control input of an external oscillator.
4 3 GND — Ground.
54f

INB

I RF prescaler complimentary input. In single-ended mode, a bypass

capacitor should be placed as close as possible to this pin and be

connected directly to the ground plane. The LMX2324 can be driven

differentially when the bypass capacitor is omitted.
65f

IN

I RF prescaler input. Small signal input from the voltage controlled oscillator.
7 6 NC No Connect
8 7 NC No Connect
9 8 OSC

in

I Oscillator input. A CMOS inverting gate input. The input has a VCC/2 input

threshold and can be driven from an external CMOS or TTL logic gate.
10 9 NC No Connect
12 10 Clock I High impedance CMOS Clock input. Data is clocked in on the rising edge,

into the various counters and registers.
13 11 Data I Binary serial data input. Data entered MSB first. LSB is control bit. High

impedance CMOS input.
14 12 LE I Load Enable input. When Load Enable transitions HIGH, data is loaded

into either the N or R register (control bit dependent). See timing diagram.
15 13 NC No Connect
11 14 NC No Connect
16 15 CE I CHIP Enable. A LOW on CE powers down the device asynchronously and

will TRI-STATE

®

the charge pump output.

116V

CC

I Power supply voltage input. Input may range from 2.7V to 5.5V. Bypass

capacitors should be placed as close as possible to this pin and be

connected directly to the ground plane.

TSSOP 16-Pin Package

DS101030-2

Order Number LMX2324TM, LM2324TMX

See NS Package Number MTC16

CSP 16-Pin Package

DS101030-3

Top View

Order Number LMX2324SLBX

See NS Package Number SLB16A

LMX2324

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Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.

Power Supply Voltage (V

CC

) −0.3V to 6.5V

Power Supply for Charge Pump (V

P

)V

CC

to 6.5V

Voltage on Any Pin with

GND=0V (V

I

) −0.3V to VCC+ 0.3V

Storage Temperature Range (T

S

) −65˚C to +150˚C

Lead Temperature (solder, 4 sec.) (T

L

) +260˚C

ESD - Human Body Model (Note 2) 2 kV

Recommended Operating
Conditions

(Note 1)

Power Supply Voltage (V

CC

) 2.7V to 5.5V

Power Supply for Charge Pump (V

P

)V

CC

to 5.5V

Operating Temperature (T

A

) −40˚C to +85˚C

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to
the device may occur. Recommended Operating Conditions indicate condi­tions for which the device is intended to be functional, but do not guarantee
specific performance limits. For guaranteed specifications and test condi­tions, see the Electrical Characteristics.

Note 2: This device is a high performance RF integrated circuit and is ESD
sensitive. Handling and assembly of this device should on be done on ESD
protected workstations.

Electrical Characteristics (V

CC

=

3V, V

P

=

3V; −40˚C

<

T

A

<

85˚C except as specified).

Symbol Parameter Conditions Min Typ Max Units

GENERAL

I

CC

Power Supply Current VCC= 2.7V to 5.5V 3.5 mA

I

CC

-PWDN Power Down Current 10 µA

f

IN

fINOperating Frequency 0.1 2.0 GHz

OSC

in

Oscillator Operating Frequency 5 40 MHz

f

PD

Phase Detector Frequency 10 MHz

Pf

IN

Input Sensitivity f

INB

grounded

through a 10 pF capacitor

VCC= 3.0V −15 0

dBm

V

CC

= 5.0V −10 0

V

OSC

Oscillator Sensitivity 0.4 1.0 VCC−0.3 V

PP

CHARGE PUMP

ICP

o-source

Charge Pump Output Current VCPo=VP/2 −4.0 mA

ICP

o-sink

4.0 mA

ICP

o-Tri

Charge Pump TRI-STATE
Current

0.5 ≤ VCPo≤ VP- 0.5
T = 25˚C

0.1 nA

ICP

o

vs.

VCP

o

Charge Pump Output Current
Variation vs. Voltage (Note 4)

0.5 ≤ VCPo≤ VP- 0.5
T = 25˚C

10

%

ICP

o-sink

vs.

ICP

o-source

Charge Pump Output Current
Sink vs. Source Mismatch
(Note 4)

VCP

o=VP

/2

T = 25˚C 5

%

ICP

o

vs. T Charge Pump Output Current

Magnitude Variation vs.
Temperature (Note 4)

VCP

o=VP

/2

−40˚C ≤ T ≤ +85˚C 10

%

DIGITAL INTERFACE (DATA, CLK, LE, CE)

V

IH

High-Level Input Voltage (Note 3) 0.8 V

CC

V

V

IL

Low-Level Input Voltage (Note 3) 0.2 V

CC

V

I

IH

High-Level Input Current VIH=VCC= 5.5V −1.0 1.0 µA

I

IL

Low-Level Input Current VIL=0,VCC= 5.5V −1.0 1.0 µA

I

IH

Oscillator Input Current VIH=VCC= 5.5V 100 µA

I

IL

VIL=0,VCC= 5.5V −100 µA

MICROWIRE TIMING

t

CS

Data to Clock Set Up Time See Data Input Timing 50 ns

t

CH

Data to Clock Hold Time See Data Input Timing 10 ns

t

CWH

Clock Pulse Width High See Data Input Timing 50 ns

t

CWL

Clock Pulse Width Low See Data Input Timing 50 ns

t

ES

Clock to Enable Set Up Time See Data Input Timing 50 ns

t

EW

Enable Pulse Width See Data Input Timing 50 ns

Note 3: Except fINand OSC

in

Note 4: See related equations in charge pump current specification definitions

LMX2324

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Charge Pump Current Specification Definitions

DS101030-4

I1=CP sink current at VCP

o

=

V

P

− ∆V

I2=CP sink current at VCP

o

=

V

P

/2

I3=CP sink current at VCP

o

=

∆V

I4=CP source current at VCP

o

=

V

P

− ∆V

I5=CP source current at VCP

o

=

V

P

/2

I6=CP source current at VCP

o

=

∆V

∆V=Voltage offset from positive and negative rails. Dependent on VCO tuning range relative to V

P

and ground. Typical values are between 0.5V and 1.0V.

1. ICP

o

vs. VCP

o

=

Charge Pump Output Current magnitude variation vs. Voltage

=

[

1

⁄

2

*

{|I1| − |I3|}]/[1⁄

2

*

{|I1| + |I3|}]*100%and [1⁄

2

*

{|I4| − |I6|}]/[1⁄

2

*

{|I4| + |I6|}]*100

%

2. ICP

o-sink

vs. ICP

o-source

=

Charge Pump Output Current Sink vs. Source Mismatch

=

[|I2| − |I5|]/[

1

⁄

2

*

{|I2| + |I5|}]*100

%

3. ICP

o

vs. T=Charge Pump Output Current magnitude variation vs. Temperature

=

[|I2

@

temp| − |I2@25˚C|]/|I2@25˚C|*100%and [|I5@temp| − |I5@25˚C|]/|I5@25˚C|*100

%

LMX2324

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