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Zarlink Semiconductor Inc.

Zarlink, ZL and the Zarlink Semiconductor logo are trademarks of Zarlink Semiconductor Inc.

Copyright 2003-2007, Zarlink Semiconductor Inc. All Rights Reserved.

Features

• Wide dynamic range (50 dB) DTMF Receiver

• Call progress (CP) detection via cadence

indication

• 4-bit synchronous serial data output

• Software controlled guard time for ZL490x0

• Internal guard time circuitry for ZL490x1

• Powerdown option (ZL4901x & ZL4903x)

• 3.579 MHz crystal or ceramic resonator (ZL4903x

and ZL4902x)

• External clock input (ZL4901x)

• Guarantees non-detection of spurious tones

Applications

• Integrated telephone answering machine

• End-to-end signalling

•Fax Machines

Description

The ZL490xx is a family of high performance DTMF

receivers which decode all 16 tone pairs into a 4-bit

binary code. These devices incorporate an AGC for

wide dynamic range and are suitable for end-to-end

signalling. The ZL490x0 provides an early steering

(ESt) logic output to indicate the detection of a DTMF

signal and requires external software guard time to

validate the DTMF digit. The ZL490x1, with preset

internal guard times, uses a delay steering (DStD)

logic output to indicate the detection of a valid DTMF

digit. The 4-bit DTMF binary digit can be clocked out

synchronously at the serial data (SD) output. The SD

pin is multiplexed with call progress detector output. In

the presence of supervisory tones, the call progress

detector circuit indicates the cadence (i.e., envelope)

of the tone burst. The cadence information can then be

processed by an external microcontroller to identify

February 2007

Ordering Information

ZL49010/11DAA

8 Pin PDIP

Tubes

ZL49020/21DAA

8 Pin PDIP

Tubes

ZL49030/31DCA

18 Pin SOIC

Tubes

ZL49030/31DCB

18 Pin SOIC

Tape & Reel

ZL49030/31DDA

20 Pin SSOP Tubes

ZL49030/31DDB

20 Pin SSOP Tape & Reel

ZL49010/11DAA1 8 Pin PDIP*

Tubes

ZL49020/21DAA1 8 Pin PDIP*

Tubes

ZL49030/31DCE1 18 Pin SOIC* Tubes, Bake & Drypack

ZL49030/31DCF1 18 Pin SOIC* Tape & Reel,

Bake & Drypack

ZL49030/31DDE1 20 Pin SSOP* Tubes, Bake & Drypack

ZL49030/31DDF1 20 Pin SSOP* Tubes, Bake & Drypack

*Pb Free Matte Tin

-40

°C to +85°C

ZL49010/11, ZL49020/21, ZL49030/31

Wide Dynamic Range DTMF Receiver

Data Sheet

Figure 1 - Functional Block Diagram

VDD

VSS

OSC2

1. ZL49010/1 and ZL49030/1 only.

2. ZL49020/1 and ZL49030/1 only.

Voltage

Bias Circuit

AGC

Anti-

alias

Filter

High

Group

Filter

Low

Group

Filter

Steering

Circuit

Digital

Detector

Algorithm

Code

Converter

and

Latch

Digital

Guard

Parallel to

Serial

Converter

& Latch

Mux

Energy

Detection

Oscillator

and

Clock

Circuit

To All Chip Clocks

Dial

Tone

Filter

ESt

DStD

ACK

SD

1

2

or

3. ZL490x1 only.

PWDN

OSC1

(CLK)