ISD4003 series high fidelity voice recording and playback IC[Copy link]
The ISD4003 series has an operating voltage of 3V, a single-chip recording and playback time of 4 to 8 minutes, and good sound quality. It is suitable for mobile phones and other portable electronic products. The chip adopts CMOS technology, and contains an oscillator, anti-aliasing filter, smoothing filter, audio amplifier, automatic squelch and high-density multi-level flash storage display. The chip design is based on the fact that all operations must be controlled by a microcontroller, and the operation commands can be sent in through a serial communication interface (SPI or Microwire). The chip adopts multi-level direct analog storage technology, and each sample value is directly stored in the on-chip flash memory, so it can reproduce voice, music, tone and effect sound very realistically and naturally, avoiding the quantization noise and "metal sound" caused by quantization and compression of general solid-state recording circuits. The sampling frequency can be 4.0, 5.3, 6.4, 8.0kHz. The lower the frequency, the longer the recording and playback time, but the sound quality is reduced. The on-chip information is stored in the flash memory, which can be saved for 100 years (typical value) in the case of power failure, and can be recorded repeatedly 100,000 times.