GENERAL DESCRIPTION

The MS87V1021 is a single chip recording and playback IC that is controlled by the microcontroller in serial mode, compresses voice with the 4-bit OKI ADPCM algorithm or 4-bit OKI ADPCM2 algorithm with high tone quality, and has 2-Mbit DRAM in which recorded data is stored and 512-Kbit mask ROM in which fixed messages reside. The MS87V1021 includes such features as Normal Recording and Playback, Delayed playback, Retroactive playback, Fast forwarding, and Rewinding.

The internal memory in which voice data is stored allows a recording/playback system to be constructed merely by externally connecting it to a microphone, a speaker driving amplifier, and a speaker.

FEATURES

? Serial microcontroller interface (clock synchronized)

? Built-in 512-Kbit mask ROM for fixed messages

ROM playback time :

Approx. 15 seconds (Fsam = 8.0 kHz)

Approx. 20 seconds (Fsam = 6.4 kHz)

Approx. 30 seconds (Fsam = 4.0 kHz)

? Voice analyzing and synthesizing system :

4-bit OKI ADPCM or 4-bit OKI ADPCM2 algorithm

8-bit OKI non-linear PCM algorithm (for ROM playback only)

? Sampling frequency (source oscillation frequency: 4.096 MHz) :

4.0 kHz, 5.3 kHz, 6.4 kHz, 8.0 kHz, or 10.6 kHz

? Recording time:

Approx. 60 seconds (Fsam = 8.0 kHz)

Approx. 80 seconds (Fsam = 6.4 kHz)

Approx. 120 seconds (Fsam = 4.0 kHz)

? Built-in 14-bit A-to-D and D-to-A converters

? Built-in LPF: Attenuation rate –40 dB/oct

? Number of phrases

Variable message: 255 phrases

Fixed phrases: 255 phrases

? Source oscillation frequency: 4.096 MHz

? Supply voltage: 2.7 to 3.6 V

? Operating current:

15 mA max. (source oscillation frequency : 4.096 MHz, Supply voltage : 3.6 V)

? Operating temperature: –20 to +70° C

? Package: 32-pin TSOP Type I