REV. 0

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ADF4212L

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781/329-4700

www.analog.com

Fax: 781/326-8703

© Analog Devices, Inc., 2002

Dual Low Power PLL

Frequency Synthesizer

FUNCTIONAL BLOCK DIAGRAM

12-BIT IF

B-COUNTER

6-BIT IF

A-COUNTER

IF

PRESCALER

OUTPUT

MUX

IF

LOCK

DETECT

CHARGE

PUMP

RF

LOCK

DETECT

CHARGE

PUMP

14-BIT RF

R-COUNTER

14-BIT IF

R-COUNTER

OSCILLATOR

22-BIT

DATA

REGISTER

SDOUT

12-BIT RF

B-COUNTER

6-BIT RF

A-COUNTER

RF

PRESCALER

IF PHASE

FREQUENCY

DETECTOR

ADF4212L

CLOCK

DATA

LE

MUXOUT

REFERENCE

IF CURRENT

SETTING

IFCP3 IFCP2 IFCP1

REFERENCE

RFCP3 RFCP2 RFCP1

REFERENCE

RF PHASE

FREQUENCY

DETECTOR

FEATURES

Bandwidth RF/IF, 2.4 GHz/1.0 GHz

2.7 V to 3.3 V Power Supply

Programmable Dual Modulus Prescaler

RF and IF: 8/9, 16/17, 32/33, 64/65

Programmable Charge Pump Currents

3-Wire Serial Interface

Analog and Digital Lock Detect

Fastlock Mode

Power-Down Mode

20-Lead TSSOP and 20-Lead MLF Chip Scale Package

APPLICATIONS

Wireless Handsets (GSM, PCS, DCS, CDMA, WCDMA)

Base Stations for Wireless Radio (GSM, PCS, DCS,

CDMA, WCDMA)

Wireless LANS

Cable TV Tuners (CATV)

Communications Test Equipment

GENERAL DESCRIPTION

The ADF4212L is a dual frequency synthesizer that can be used

to implement local oscillators (LO) in the up-conversion and

down-conversion sections of wireless receivers and transmitters.

It can provide the LO for both the RF and IF sections. It con-

sists of a low noise digital PFD (Phase Frequency Detector), a

precision charge pump, a programmable reference divider, pro-

grammable A and B counters, and a dual modulus prescaler

(P/P + 1). The A (6-bit) and B (12-bit) counters, in conjunction

with the dual modulus prescaler (P/P + 1), implement an N

divider (N = BP + A). In addition, the 14-bit reference counter

(R Counter), allows selectable REFIN frequencies at the PFD

input. A complete PLL (Phase-Locked Loop) can be imple-

mented if the synthesizer is used with external loop filters and

VCOs (Voltage Controlled Oscillators).

Control of all the on-chip registers is via a simple 3-wire interface

with 1.8 V compatibility. The devices operate with a power

supply ranging from 2.6 V to 3.3 V and can be powered down

when not in use.