SSM2166 Complete Microphone Conditioner with Variable Compression & Noise Gating

Microphone preamplifiers/processors Computer sound cards Public address/paging systems Communication headsets Telephone conferencing Guitar sustain effects generators Computerized voice recognition Surveillance systems Karaoke and DJ mixers

The SSM2166 integrates a complete and flexible solution for conditioning microphone inputs in computer audio systems. It is also excellent for improving vocal clarity in communications and public address systems. A low noise, voltage-controlled amplifier (VCA) provides a gain that is dynamically adjusted by a control loop to maintain a set compression characteristic. The compression ratio is set by a single resistor and can be varied from 1:1 to over 15:1 relative to a user-defined rotation point; signals above the rotation point are limited to prevent overload and to eliminate popping. In the 1:1 compression setting, the SSM2166 can be programmed with a fixed gain of up to 20 dB; this gain is in addition to the variable gain in other compression settings. The input buffer can also be configured for front-end gains of 0 dB to 20 dB. A downward expander (noise gate) prevents amplification of noise or hum. This results in optimized signal levels prior to digitization, thereby eliminating the need for additional gain or attenuation in the digital domain that could add noise or impair accuracy of speech recognition algorithms. The compression ratio and time constants are set externally. A high degree of flexibility is provided by the VCA gain, rotation point, and noise gate adjustment pins.

The SSM2166 is an ideal companion product for audio codecs used in computer systems. The SSM2166 is available in a 14-lead SOIC package and is guaranteed for operation over the extended industrial temperature range of −40°C to +85°C.

Applications

Features and Benefits
  • Complete microphone conditioner in a 14-lead package
  • Single 5 V operation
  • Adjustable noise gate threshold
  • Compression ratio set by external resistor
  • Automatic limiting feature—prevents ADC overload
  • Adjustable release time
  • Low noise and distortion
  • Power-down feature
  • 20 kHz bandwidth (±1 dB)
  • Audio & Video Products
    Security and Surveillance
    • Asset Tracking
    Data Sheets
    Documentnote
    SSM2166: Microphone Preamplifier with Variable Compression and Noise Gating Data Sheet (Rev. F)PDF 430.88 K
    Application Notes
    Documentnote
    AN-938: Digital and Analog Measurement Units for Digital CMOS Microphone Preamplifier ASICs (Rev. 0)PDF 75 kB
    AN-583: Evaluating the SSM2167 Low Voltage Microphone Preamplifier with Variable Compression and Noise GatingPDF 132 kB
    Order Information
    Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
    SSM2166SZ Production14 ld SOICOTH 56-40 to 85C3.413.13Y
    SSM2166SZ-REEL Production14 ld SOICREEL 2500-40 to 85C03.13Y
    SSM2166SZ-REEL7 Production14 ld SOICREEL 1000-40 to 85C03.13Y
    SSM2166: Microphone Preamplifier with Variable Compression and Noise Gating Data Sheet (Rev. F) ssm2166
    AN-938: 数字CMOS麦克风前置放大器ASIC的数字和模拟测量单位 (Rev. 0) ssm2166
    AN-938: Digital and Analog Measurement Units for Digital CMOS Microphone Preamplifier ASICs (Rev. 0) ssm2166
    AN-583: Evaluating the SSM2167 Low Voltage Microphone Preamplifier with Variable Compression and Noise Gating ssm2166