BK-21968-000

Overview

The Knowles BK-21968-000 is a balanced armature receiver designed for high-sensitivity audio applications. It features a magnetic impedance of 730 Ohms and delivers a sound pressure level of 123 dBA. The component operates within a frequency range of 200 Hz to 3.8 kHz, with a self-resonant frequency at 3.8 kHz. It utilizes solder pad termination and measures 0.310 inches (7.87 mm) in length by 5.59 mm in width.

Feature Summary

• High sensitivity output capability for efficient audio reproduction
• Balanced armature transducer technology for precise acoustic performance
• Side port configuration for directional sound projection

Applications

• Hearing aids requiring compact high-output receivers
• Medical diagnostic equipment needing precise audio feedback
• Industrial communication devices demanding clear signal transmission

Procurement Notes

Verify the specific port orientation (side vs. top) and exact SPL rating against the manufacturer's latest datasheet, as sources indicate variations between 123 dB and 126 dB. Confirm impedance consistency at 730 Ohms. Ensure the solder pad termination style matches your PCB layout requirements before finalizing procurement orders.

Selection Notes

Select this component when high acoustic efficiency is critical within a constrained physical footprint. The 730 Ohm impedance suits specific driver circuits requiring higher voltage drive levels. Consider the 200 Hz to 3.8 kHz bandwidth to ensure it covers the necessary speech or alert frequencies for the target application without excessive external filtering.

Part Context

This part belongs to Knowles' portfolio of precision acoustic components, specifically their balanced armature receivers. These components are engineered for miniaturized electronic devices where space is limited but audio clarity and volume are paramount. The BK series typically targets medical and industrial sectors requiring reliable, long-life acoustic solutions.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. Verify compatibility with existing driver circuits if considering alternative balanced armature receivers from other manufacturers.