SPH9855LM4H-1

Overview

The SPH9855LM4H-1 is a digital MEMS microphone from the Sisonic family, manufactured by Syntiant. It features a bottom port configuration and delivers a signal-to-noise ratio of 66 dBA with an acoustic overload point of 132.5 dB SPL. The device operates at a supply voltage of 1.8 V, offering low power consumption of 260 uA and standard mode current of 1000 uA. It provides a sensitivity of -37 +/-1 dBV and maintains a power supply rejection ratio of 86 dB PSRR. The frequency response begins at 25 Hz.

Feature Summary

• Integrates high signal-to-noise ratio performance with exceptional acoustic overload capability for clear audio capture in demanding environments.
• Features a bottom port design that facilitates robust mounting on printed circuit boards while protecting the acoustic sensor.
• Delivers digital PDM output to simplify system integration and reduce analog noise susceptibility in digital processing chains.

Applications

• Voice recognition systems requiring high fidelity input
• Smart home devices needing reliable far-field audio capture
• Wearable technology constrained by low power budgets

Procurement Notes

Verify component authenticity through authorized distributors or direct manufacturer channels. Confirm RoHS compliance status and humidity sensitivity handling requirements during storage and assembly. Ensure ordering quantities align with available packaging formats such as cut tape or reel specifications provided by the supplier.

Selection Notes

Evaluate the trade-off between low power mode and standard performance based on application battery constraints. Consider the bottom port orientation relative to the device enclosure design to ensure optimal acoustic coupling. Verify compatibility with host processor interfaces supporting digital PDM signals.

Part Context

This component belongs to the Sisonic series of silicon microphones designed for mobile and IoT applications. It represents a shift towards fully digital sensing solutions that integrate signal conditioning directly onto the MEMS die. The product line emphasizes miniaturization and enhanced acoustic metrics compared to traditional analog counterparts.

Replacement Considerations

Consult official Syntiant documentation for verified substitute part numbers within the same Sisonic family. Cross-reference pinouts and electrical characteristics before implementing any alternative components to ensure functional compatibility.