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Zarlink Semiconduc tor Inc.
Zarlink, ZL and the Zarlink Semiconductor logo are trademarks of Zarlink Semiconductor Inc.
Copyright 2003, Zarlink Semiconductor Inc. All Rights Reserved.
Features
• Wide dynamic range (50dB) 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)
• 3.579MHz crystal or ceramic resonator (ZL4903x
and ZL 4902 x)
• External clock input (ZL4901x)
• Guarantees non-detection of spurious tones
Applicatio ns
• Integrated telephone answering machine
• End-to-end signalling
• Fax Ma chi nes
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
synchr onously at the s erial data (SD) outpu t. The SD
pin is multiplexed with call progress detector output. In
the presence of supervisory tones, the call progress
September 2003
Ordering Information
ZL49 01 0 DA A 8 Pi n P DIP Tubes
ZL49 011DAA 8 Pi n P DIP Tubes
ZL49 02 0 DA A 8 Pi n P DIP Tubes
ZL49021DAA 8 Pin PDIP Tubes
ZL49 03 0 DCA 18 P i n SOI C Tubes
ZL49030DCB 18 Pin SOIC Tape & Reel
ZL49030DDA 20 Pin SSOP Tubes
ZL49030DDB 20 Pin SSOP Tape & Reel
ZL49031DCA 18 Pin SOIC Tubes
ZL49031DCB 18 Pin SOIC Tape & Reel
ZL49031DDA 20 Pin SSOP Tubes
ZL49031DDB 20 Pin SSOP Tape & Reel
-40°C to +85°C
ZL49010/1, ZL49020/1, ZL49030/ 1
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
Time
3
Parallel to
Serial
Converter
& Latch
Mux
Energy
Detection
Oscillator
and
Clock
Circuit
To All Chip Cloc k s
Dial
Tone
Filter
ESt
DStD
ACK
SD
1
2
or
3. ZL490x1 only.
PWDN
OSC1
(CLK)