SSM2166SZ-REEL7

Overview

The SSM2166SZ-REEL7 is a microphone preamplifier with variable compression and noise gating manufactured by Analog Devices Inc. It operates on a single 5 V supply (4.5 V to 5.5 V) and features a 14-lead SOIC package. The device provides a voltage-controlled amplifier with up to 60 dB dynamic gain range, adjustable compression ratios from 1:1 to over 15:1, and an input impedance of 180 kΩ. It includes a downward expander for noise reduction, power-down functionality reducing current to under 100 µA, and a bandwidth of 20 kHz.

Feature Summary

• Integrates complete microphone conditioning including amplification, automatic limiting, variable compression, and downward expansion.
• Features a low-noise voltage-controlled amplifier with adjustable compression ratio and user-defined rotation point to prevent overload.
• Includes a downward expander to eliminate circuit noise in the absence of an input signal.
• Provides a power-down feature that significantly reduces supply current.

Applications

• Microphone preamplifiers and processors
• Computer sound cards
• Public address and paging systems
• Communication headsets
• Telephone conferencing

Procurement Notes

Verify the specific suffix REEL7 indicates reel packaging when confirming order details. Ensure the component matches the 14-lead SOIC physical outline. Confirm the manufacturer is Analog Devices Inc. Check availability status as distribution may vary. Validate RoHS compliance requirements against project specifications before finalizing procurement.

Selection Notes

Select this component for applications requiring integrated voice-band signal conditioning. It is suitable for environments needing fixed or variable gain adjustment without external digital processing. Consider the single 5 V supply requirement and the need for external resistors to set compression ratios and thresholds. Evaluate thermal performance within the specified industrial temperature range.

Part Context

This part belongs to the SSM2166 family of audio interface components designed for analog microphone signal processing. It serves as a companion to audio codecs in computer systems, optimizing signal levels prior to digitization. The series focuses on improving vocal clarity and managing dynamic range in communication and public address applications.

Replacement Considerations

Direct substitutes are not explicitly listed in the provided documentation. Verify pin compatibility and electrical specifications if considering alternative microphone preamplifiers with similar compression and gating features.

FAQ

How is the compression ratio adjusted?

The compression ratio is set externally by connecting a resistor between the COMP RATIO SET pin (Pin 10) and ground.

What is the function of the Power Down pin?

Connecting Pin 12 to the positive supply activates power-down mode, reducing supply current to less than 100 µA. Connecting it to ground enables normal operation.

How is the noise gate threshold determined?

The downward expansion threshold is set by a resistor connected between the NOISE GATE SET pin (Pin 9) and the positive supply.