Anterwell Technology Ltd.
Anterwell Technology Ltd. Large Original stock of IC Electronics Components, Transistors, Diodes etc. High Quality, Reasonable Price, Fast Delivery.
Add to Cart
MT8870DE Very Large Scale Integrated Circuits Ics Complete DTMF Receiver
Features
• Complete DTMF Receiver
• Low power consumption
• Internal gain setting amplifier
• Adjustable guard time
• Central office quality
• Power-down mode
• Inhibit mode
• Backward compatible with MT8870C/MT8870C-1
Description
The MT8870D/MT8870D-1 is a complete 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 tonepairs 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.
Applications
• Receiver system for British Telecom (BT) or CEPT Spec (MT8870D-1)
• Paging systems
• Repeater systems/mobile radio
• Credit card systems
• Remote control
• Personal computers
• Telephone answering machine
Figure 1 - Functional Block Diagram
Figure 2 - Pin Connections
Functional Description
The MT8870D/MT8870D-1 monolithic DTMF receiver
offers small size, low power consumption and high
performance. Its architecture consists of a bandsplit
filter section, which separates the high and low group
tones, followed by a digital counting section which
verifies the frequency and duration of the received
tones before passing the corresponding code to the output bus.