ISD14B40X

Overview

The ISD14B40X is a single-chip multiple-message record/playback device from the ISD14B00 ChipCorder series. It operates on a supply voltage of 2.4V to 5.5V and supports an operating temperature range of 0°C to +50°C. The sampling frequency is selectable from 4 kHz to 12 kHz via an external resistor (Rosc), which also determines the total recording duration. For the ISD14B40 derivative, the maximum duration ranges from 21.3 seconds at 12 kHz to 64 seconds at 4 kHz. The device features dual operating modes: Address Mode for flexible message durations defined by start/end address pins, and Direct Mode for up to eight fixed-duration messages with random access. It includes a differential microphone input with Automatic Gain Control (AGC), feed-through capability, and Class-D PWM speaker drivers.

Feature Summary

• Dual operational modes allowing either flexible address-based message definition or direct mode with up to eight pre-configured fixed-duration messages for random access.
• Integrated differential microphone inputs with Automatic Gain Control (AGC) to dynamically adjust preamplifier gain for optimal signal recording.
• Direct drive Class-D PWM speaker outputs capable of driving an 8Ω speaker, with optional single-ended voltage output depending on the specific derivative.
• Automatic power-down functionality after each operation cycle to minimize standby current consumption.

Applications

• Standalone voice messaging systems
• Automated announcements and public address devices
• Educational toys and interactive learning aids
• Security alarm voice prompts

Procurement Notes

Verify the specific suffix of the part number against the official Nuvoton ordering information table to confirm pinout compatibility and package type. Ensure the selected derivative matches the required audio output configuration, as some variants provide differential speaker outputs while others offer single-ended voltage outputs. Confirm that the system design accommodates the specified operating temperature range of 0°C to +50°C.

Selection Notes

Select the ISD14B40X when a moderate recording duration between 21.3 and 64 seconds is required, depending on the chosen sampling frequency. Choose Address Mode if message lengths need to be customized via hardware address pins. Select Direct Mode if the application requires simple, fixed-length message playback with minimal control logic. Ensure the external Rosc resistor value corresponds to the desired sampling frequency and duration specifications.

Part Context

The ISD14B40X belongs to the ISD14B00 series, which differentiates itself from other ISD families by offering both Address and Direct modes in a single chip. Compared to the ISD14B20, it provides double the memory capacity, while the ISD14B80 offers four times the capacity. This series is designed for standalone applications but can also be controlled by a microcontroller if necessary.

Replacement Considerations

ISD14B20X offers similar functionality with reduced memory capacity (10.6s to 32s duration). ISD14B80X provides increased memory capacity (42.6s to 128s duration). Verify that the replacement part's audio output configuration (differential vs. single-ended) matches the existing circuit design.