M-8870-01SM

Telecom Overview

The M-8870-01SM is a DTMF receiver manufactured by IXYS Integrated Circuits Division (formerly Clare) in an 18-pin plastic SOIC package. It integrates bandsplit filters and a digital decoder to detect all 16 DTMF tone pairs, outputting a 4-bit code. The device operates on a single 5V supply with typical current of 3.0 mA and power consumption of 15 mW. It utilizes switched capacitor technology for filtering and digital counting for decoding. External components are limited to a 3.579545 MHz crystal, a timing resistor, and a capacitor.

Telecom Feature Summary

• Integrates bandsplit filter and decoder functions into a single package
• Uses switched capacitor technology for high and low group filters
• Includes on-chip differential input amplifier and clock generator
• Features latched tri-state interface bus for data output

Telecom Applications

• Telephone switch equipment
• Remote data entry systems
• Paging systems
• Personal computers
• Credit card systems

Telecom Procurement Notes

Verify the manufacturer designation as IXYS Integrated Circuits Division or Clare, Inc., depending on the production era. Confirm the -01 suffix indicates the absence of power-down and inhibit modes compared to the -02 variant. Ensure the SM suffix corresponds to the 18-pin plastic SOIC package format required for the specific PCB layout.

Telecom Selection Notes

Select this component when a complete DTMF decoding solution is needed with minimal external parts. The -01SM variant lacks power-down capabilities; use the -02SM version if standby mode is required. Designers must provide a 3.579545 MHz crystal and adjust external RC timing constants to meet specific acquisition and release time requirements.

Telecom Part Context

This part belongs to the M-8870 family of DTMF receivers. The -01SM designation specifically identifies the standard version without power-down features in an SOIC package. Other variants include DIP packages and versions with additional control modes. The device represents a CMOS-based solution for telecommunication signal processing.

Telecom Replacement Considerations

Direct substitutes include the M-8870-01SMTR (tape and reel version) and the M-8870-01 (DIP package). For functional equivalents with power-down options, consider the M-8870-02SM series. Cross-reference with other DTMF receivers like the HM9270C or HT9170 only if pin compatibility and timing characteristics are verified.