MT88L70

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


Application

• Paging systems
• Repeater systems/mobile radio
• Credit card systems
• Remote control
• Personal computers
• Telephone answering machine


Pinout

Specifications

Parameter	Symbol	Min.	Max.	Units
DC Power Supply Voltage	VDD		7	V
Voltage on any pin	VI	VSS-0.3	VDD+0.3	V
Current at any pin (other than supply)	II		10	mA
Storage temperature TSTG	TSTG	-65	+150	°C
Package power dissipation	PD		500	mW

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 MT88L70 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.