
NEC => Renesas Technology
The µPD7759 is an external ROM type speech synthesis LSI employing the waveform coding method. In addition to the ROM capability of up to 1 Mbit, the µPD7759 realizes the synthesis of speech sounds of any length by using the ADPCM data transferred from an external ROM.
As the synthesizing method, it adopts the ADPCM method and the PCM + waveform element method.
The ADPCM method is suitable for synthesizing clear and natural speech sounds, and the PCM + waveform element method is for the synthesis of sound effects and melodies. And by using them together, the µPD7759 realizes the long-time synthesis of high-quality sounds.
Because of the short turn-around time of speech analysis, the µPD7759 can perform the quick system development using a PROM, or the evaluation of an on-chip ROM type of the µPD7755 family.
FEATURES
● Synthesizing method : ADPCM, PCM + waveform element methods used together
● Sampling frequency : 5, 6 or 8 kHz
● Bit rate (speech) : 20 to 32 K bps
● Number of Messages : 256 (MAX.)
● External speech data ROM