MT88L70 Datasheet, PDF (1/16 Pages) Mitel Networks Corporation – 3 Volt Integrated DTMF Receiver

MT88L70
3 Volt Integrated DTMF Receiver
Data Sheet
Features
• 2.7 - 3.6 volt operation
• Complete DTMF receiver
• Low power consumption
• Internal gain setting amplifier
• Adjustable guard time
• Central office quality
• Power-down mode
• Inhibit mode
• Functionally compatible with Zarlink’s MT8870D
Applications
• Paging systems
• Repeater systems/mobile radio
• Credit card systems
• Remote control
• Personal computers
• Telephone answering machine
August 2005
Ordering Information
MT88L70AE
MT88L70AS
MT88L70AN
MT88L70ASR
MT88L70ANR
MT88L70AE1
MT88L70AN1
MT88L70ANR1
MT88L70AS1
MT88L70ASR1
18 Pin PDIP Tubes
18 Pin SOIC Tubes
20 Pin SSOP Tubes
18 Pin SOIC Tape & Reel
20 Pin SSOP Tape & Reel
18 Pin PDIP* Tubes
20 Pin SSOP* Tubes
20 Pin SSOP* Tape & Reel
18 Pin SOIC* Tubes
18 Pin SOIC* Tape & Reel
* Pb Free Matte Tin
-40°C to +85°C
Description
The MT88L70 is a complete 3 Volt, DTMF receiver
integrating both the bandsplit filter and digital decoder
functions. The filter section uses switched capacitor
techniques for high and low group filters; the decoder
uses digital counting techniques to detect and decode
all 16 DTMF tone-pairs into a 4-bit code. External
component count is minimized by on chip provision of
a differential input amplifier, clock oscillator and latched
three-state bus interface.
VDD VSS
VRef
INH
PWDN
Bias
Circuit
VRef
Buffer
Q1
Chip Chip
Power Bias
High Group
Filter
Digital
Code
Detection
Algorithm
Converter
and Latch
Q2
IN +
Dial
Tone
IN -
Filter
Zero Crossing
Detectors
Q3
GS
Low Group
Filter
Q4
to all
Chip
Clocks
St
Steering
GT
Logic
OSC1
OSC2
St/GT
ESt
STD
TOE
Figure 1 - Functional Block Diagram
1
Zarlink Semiconductor Inc.
Zarlink, ZL and the Zarlink Semiconductor logo are trademarks of Zarlink Semiconductor Inc.
Copyright 1997-2005, Zarlink Semiconductor Inc. All Rights Reserved.