ISD ChipCorder Voice ICs
Development Tools for ISD ChipCorders
Known under the trade name ChipCorder ICs are complete, highly integrated single chip solutions for voice and audio recording and playback. They use internal or external non-volatile memory and are ideal for adding voice/audio functions to consumer, industrial, automotive, medical and security products.
Depending on the type of memory they are divided into two following groups:
MLS ChipCorders using Nuvoton's patented Multilevel Storage (MLS) technology for recordings storage in on-chip non-volatile memory (equivalent to 8-bit digital storage). Voice and audio signals are recorded directly into memory cells in their natural form, providing high-quality voice/audio reproduction. They are designed for single/multiple messages recording and provide 6 seconds to 16 minutes record/playback durations and 4 kHz to 12 kHz sampling frequency (industry-leading sound quality). They can operate in either standalone mode with the parallel push-button interface or a microcontroller mode with the SPI or I2C serial interface. Some devices incorporate an intelligent message management system that allows to self-manage address locations for multiple messages. This feature is used in simple push-button solutions.
The devices include an internal oscillator, analog input and/or microphone preamplifier with AGC and also a class AB/D speaker driver and current/voltage output.
More about MLS technology
Digital ChipCorders using an internal or external digital Flash memory for voice/audio storage, designed for multi-message recording/playback or playback-only applications. In the latter case the messages prepared in the form of digital data by means of an external device and pre-recorded in the memory via digital audio interface are played. The message management system allows users to make address-free recording for multiple messages.
Digital ChipCorders provide an I2S digital audio interface and SPI interface for commands and digital audio data. They feature 2/3/4/5-bit ADPCM and 8/10/12-bit PCM digital compressions, 6/7/8-bit µ-Law/differential µ-Law companding, comprehensive memory management to storage a pre-recorded audio data, and integrated analog/digital audio signal paths with analog inputs/outputs, microphone preamplifier with AGC and class AB or D speaker driver. They provide 15 seconds to 64 minutes record/playback durations (based on 8 kHz / 4-bit ADPCM) and an audio quality sound with up to 48 kHz sampling frequency and SNR of 60 dB (equivalent to 12-bit resolution).
Compared to the MLS ChipCorder series, Digital ChipCorders provide higher sampling frequencies, better sound quality, lower power consumption and fast programming time.