CI-28204-000

Overview

The Knowles CI-28204-000 is a balanced armature receiver speaker designed for surface-mount applications. It features a top rectangular port configuration and operates within a frequency range of 200 Hz to 5.5 kHz. The component has an electrical impedance of 264 Ohms and delivers a sound pressure level of 131.5 dB. Manufactured by Knowles, this transducer is classified under speakers and transducers, suitable for compact audio output requirements in portable electronic devices.

Feature Summary

• Balanced armature transducer technology for high-fidelity audio reproduction
• Top rectangular port design for directed sound projection
• High sensitivity rating of 131.5 dB for efficient acoustic output
• Surface-mount construction for automated PCB assembly

Applications

• Portable consumer electronics audio output
• Medical device acoustic signaling
• Industrial communication equipment receivers

Procurement Notes

Verify the specific impedance variant (264 Ohms) against system requirements, as datasheets may list similar models with different impedances like 400 Ohms. Confirm the port orientation (top vs. side) matches the enclosure design. Ensure RoHS compliance status is documented for regulatory adherence. Cross-reference the manufacturer part number directly with official Knowles documentation to avoid confusion with generic equivalents.

Selection Notes

Select this component when a high-sensitivity, low-profile balanced armature speaker is required for space-constrained designs. The 264 Ohm impedance suits specific driver circuits. Consider the 200 Hz to 5.5 kHz frequency response for voice or alert tones rather than full-range music. Verify mechanical mounting constraints due to the rectangular form factor.

Part Context

Knowles is a recognized manufacturer of precision acoustic components. The CI series represents their line of balanced armature speakers. This model falls under the broader category of surface-mount transducers used in modern miniaturized electronics where size and performance are critical.

Replacement Considerations

Direct substitutes include other Knowles balanced armature speakers with matching 264 Ohm impedance and 131.5 dB sensitivity. Check for identical dimensional tolerances and port location (top rectangular) to ensure mechanical compatibility without enclosure modification.