BL-21994-000

Overview

The Knowles BL-21994-000 is a piezoelectric analog microphone designed for omnidirectional sound capture. It features a 4 kOhms impedance and operates with a current rating of 160 uA. The device provides an acoustic frequency response range of 20 Hz to 10 kHz, ensuring effective audio signal detection across standard voice bands. Sensitivity specifications indicate a performance level of -69dB ±3dB when measured at a sound pressure level of 74dB SPL. The component utilizes wire leads for connection, facilitating integration into various electronic assemblies requiring reliable analog audio input.

Feature Summary

• Piezoelectric transduction mechanism for analog audio signal generation
• Omnidirectional directional properties for uniform sound pickup
• Wire lead termination for direct circuit integration

Applications

• Voice recognition systems
• Consumer audio recording devices
• Industrial noise monitoring equipment

Procurement Notes

Verify the specific datasheet version from Knowles Electronics to confirm RoHS compliance status and exact mechanical dimensions prior to finalizing procurement. Ensure that the wire lead configuration matches the target assembly requirements. Cross-reference the impedance and sensitivity parameters against the system design specifications to guarantee compatibility with the intended amplifier or processing circuitry.

Selection Notes

Select this component when an omnidirectional piezoelectric microphone is required for analog audio applications. The 4 kOhms impedance and 160 uA current rating define the electrical interface characteristics. Consider the 20 Hz to 10 kHz frequency response for suitability in voice-centric environments. The wire lead format dictates the mounting and soldering approach within the host device enclosure.

Part Context

This part belongs to the Knowles piezoelectric microphone family, which specializes in compact acoustic sensors. These components are engineered for cost-effective mass production while maintaining consistent acoustic performance. The BL-21994-000 represents a standard offering within this portfolio, focusing on general-purpose analog audio capture rather than specialized high-fidelity or digital output applications.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. Verify compatibility with alternative models by matching the piezoelectric type, omnidirectional pattern, and electrical parameters such as 4 kOhms impedance and -69dB sensitivity.