ISD2540SR

Overview

The ISD2540SR is a single-chip, multiple-message voice record/playback device from the Winbond ISD2500 series. It provides a recording duration of 40 seconds using on-chip nonvolatile multilevel storage array technology. The CMOS device integrates an on-chip oscillator, microphone preamplifier with automatic gain control, antialiasing and smoothing filters, and a speaker amplifier. It operates on a single 5V power supply and supports microcontroller or manual switch interfaces. The SR suffix indicates availability in die form for commercial temperature ranges (0°C to +50°C). Recordings are stored directly into memory without digitization, ensuring high-quality natural voice reproduction.

Feature Summary

• Single-chip solution integrating analog transceivers, nonvolatile storage, and digital control logic.
• Direct analog storage of voice signals into on-chip EEPROM for natural audio reproduction.
• Microcontroller compatible interface allowing complex messaging and addressing.
• Supports multiple operational modes including push-button control and message cueing.

Applications

• Car stereo voice prompts
• Handset answering machines
• Transformer-based voice modules

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current datasheet to confirm package type and temperature grade. The 'SR' designation typically corresponds to the die form factor within the ISD2540 product family. Ensure compatibility with system voltage requirements and interface protocols before integration. Cross-reference part numbers with official distributor catalogs to confirm availability and revision status.

Selection Notes

Select this component for applications requiring up to 40 seconds of uncompressed voice recording. Consider the ISD2532 for shorter durations with higher sampling rates or the ISD2564 for longer playback times. Evaluate the need for external clocking versus internal oscillator precision based on application requirements. Verify that the system can accommodate the separate analog and digital ground connections required for optimal noise performance.

Part Context

This device belongs to the Winbond ISD2500 ChipCorder series, which utilizes patented multilevel storage technology. The series includes variants with 32, 48, and 64-second durations. These devices are designed as standalone solutions for voice messaging, eliminating the need for external microcontrollers or compression algorithms. The technology allows for direct analog-to-memory storage, distinguishing it from standard digital voice ICs.

Replacement Considerations

Direct pin-compatible replacements within the same series include ISD2532, ISD2548, and ISD2564, depending on required duration. For different manufacturers, evaluate ISD16xx series devices, noting differences in interface and packaging. Verify that any substitute maintains the single-supply operation and nonvolatile storage characteristics.