ISD4002-240EYI

Overview

The ISD4002-240EYI is a single-chip voice record and playback device from the Nuvoton ISD4002 ChipCorder series. It provides 240 seconds of recording duration at a sampling frequency of 4.0 kHz, with a typical filter pass band of 1.7 kHz. The component operates on a single 3-volt supply (2.7 V to 3.3 V) and features low-power consumption, including a standby current of 1 µA. It utilizes an SPI interface for control and contains non-volatile multilevel Flash memory capable of 100,000 record cycles. The device is packaged in a 28-SOIC format.

Feature Summary

• Direct analog storage of voice signals into non-volatile Flash memory without digitization or compression.
• AutoMute feature minimizes background noise during silence periods by attenuating output.
• Fully addressable architecture allows handling of multiple messages via microcontroller SPI interface.
• Integrated on-chip oscillator, anti-aliasing filter, smoothing filter, and audio amplifier.

Applications

• Portable consumer electronics requiring brief voice messaging capabilities
• Industrial equipment monitoring systems with automated voice alerts
• Security alarm systems utilizing direct speech transmission instead of simple tones

Procurement Notes

Verify the specific suffix 'EYI' against the manufacturer's official ordering guide to confirm package type and temperature range specifications. Ensure the design supports the required external clock frequency if higher precision than the internal oscillator is needed for the 4.0 kHz sampling rate.

Selection Notes

Select this model when a 240-second maximum recording time is required. Note that the lower sampling rate of 4.0 kHz results in reduced audio fidelity compared to shorter duration variants. Verify that the system power supply remains within the 2.7 V to 3.3 V operating range to ensure correct functionality.

Part Context

This component belongs to the ISD4002 ChipCorder series, which offers durations ranging from 120 to 240 seconds. Unlike digital voice chips, it stores analog waveforms directly, simplifying the interface requirements while maintaining natural voice reproduction quality suitable for standard telephony bandwidth applications.

Replacement Considerations

ISD4002-120SY: Offers 120 seconds duration at 8.0 kHz sampling rate.

FAQ

What is the recommended external clock frequency for the ISD4002-240 variant?

For the ISD4002-240 model operating at a 4.0 kHz sampling rate, the datasheet recommends an external clock input of 512 kHz via the XCLK pin for improved stability.

How does the AutoMute feature function?

The AutoMute feature detects signal amplitude using an internal peak detector. During silence, it applies 6 dB of attenuation to minimize background noise, while automatically disabling attenuation for large signals.

What is the memory retention capability of the device?

The on-chip multilevel Flash memory retains recorded messages for up to 100 years typically without power application.