ISD4002-120S

Overview

The ISD4002-120S is a single-chip voice record/playback device from the ISD4002 series, designed for portable applications requiring high-quality audio. It features on-chip Flash memory storing analog speech samples directly without digitization or compression. The device operates on a single 3V supply and includes an internal oscillator, anti-aliasing filter, smoothing filter, and audio amplifier. Control is managed via a Serial Peripheral Interface (SPI) or Microwire interface. For the ISD4002-120S variant, the sampling frequency is 8.0 kHz, providing a typical record and playback duration of 120 seconds with a filter pass band of 3.4 kHz.

Feature Summary

• Direct analog storage of voice signals into non-volatile Flash memory for high-fidelity reproduction
• Integrated AutoMute feature to attenuate background noise during silence periods
• Fully addressable memory architecture allowing multiple message handling via SPI control
• Zero-power message storage capability with long-term retention characteristics

Applications

• Cellular phone messaging systems
• Portable electronic devices requiring voice prompts
• Microcontroller-based intercom or announcement systems
• Automotive voice guidance modules

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official datasheet to confirm package type and temperature grade. Ensure the selected variant matches the required operating environment, as commercial, extended, and industrial grades have distinct temperature ranges. Confirm pin compatibility if substituting within the ISD4002 series, noting that duration variants differ in sampling rates.

Selection Notes

Select the ISD4002-120S when a 120-second recording capacity at 8.0 kHz sampling rate is required. Higher duration models (150s, 180s, 240s) utilize lower sampling frequencies, which reduces audio bandwidth. Ensure the host microcontroller supports the required SPI protocol and can handle the specified power-up delay times. Verify that the application can accommodate the separate analog and digital ground requirements for optimal signal integrity.

Part Context

The ISD4002-120S belongs to the ISD4002 ChipCorder series, which offers durations ranging from 120 to 240 seconds. This series utilizes Winbond’s multilevel Flash technology to store analog waveforms directly. Other members include the ISD4002-150, ISD4002-180, and ISD4002-240, each offering different trade-offs between recording time and audio quality based on their respective sampling rates.

Replacement Considerations

Compatible substitutes within the same family include the ISD4002-150, ISD4002-180, and ISD4002-240. These parts share identical pinouts and control interfaces but differ in sampling frequency and maximum duration. Substitution requires verifying that the reduced sampling rate of higher-duration models meets the audio quality requirements of the application.

FAQ

How does the ISD4002-120S handle audio input?

The device accepts audio via ANA IN+ and ANA IN- pins, supporting both single-ended (32 mVp-p max) and differential (16 mVp-p max) input modes. External capacitors are required to set the low-frequency cutoff.

What is the function of the RAC pin?

The Row Address Clock (RAC) pin provides a periodic signal indicating the end of a memory row. It is used for memory management techniques, such as determining when to update the address pointer during continuous operations.

Can the ISD4002-120S operate without a microcontroller?

No, the device requires a master controller (microprocessor or microcontroller) to generate the SPI clock and send opcodes for power-up, record, and playback commands.