Features

–AM

≥ 1 kHz

–FM

≥ 2 kHz

1.

Description

The ATR4289 is an integrated circuit in BiCMOS technology for frequency synthesiz-

ers. It performs all the functions of a PLL radio tuning system and is controlled by a

2-wire bus. The device is designed for all frequency synthesizer applications in radio

receivers, as well as for radio data system (RDS) applications.

Figure 1-1.

Block Diagram

R divider

N divider

interface

Oscillator

Phase

Current

sources

AM/FM

14

15

2

3

4

6

8

OSCOUT

OSCIN

SCL

AS

FMOSC

AMOSC

SDA

5

7

1

16

SWO1

11

12

13

9

10

PDAM

PDAMO

VA

PDFMO

PDFM

GND2

GND1

VDD

switch

Switching

output

detector

AM/FM PLL with

1 Switch

ATR4289

Rev. 4885A–AUDR–09/05