MOS INTEGRATED CIRCUIT

ADPCM SPEECH SYNTHESIZER LSIs

Please refer to "Quality grade on NEC Semiconductor Devices" (Document number IEI-1209) published by

NEC Corporation to know the specification of quality grade on the devices and its recommended applications.

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

q Synthesizing method

: ADPCM, PCM + waveform element methods used together

q Sampling frequency

: 5, 6 or 8 kHz

q Bit rate (speech)

: 20 to 32 K bps

q Number of Messages

: 256 (MAX.)

q External speech data ROM

Parameters

Synthesizing time

Products

(PCM + waveform element)

µPD7759

1 Mbits

50 sec. (TYP.)

340 sec. (TYP.)

Note 1.

The synthesizing time for the speech is the value for a 6 kHz sampling.

2.

The synthesizing time for the melodies & sound effects is variable according to their tone.

q Speech output

: Current sink type analog output, 9-bit D/A converter

q Host CPU interface

: Compatible with a 4/8-bit CPU

q Standby mode

: Pop-noise preventive circuit incorporated

q Supply voltage

: 2.7 to 5.5 V

q CMOS technology

ORDERING INFORMATION

Part Number

Package

Quality grade

µPD7759C

40-pin plastic DIP (600 mil)

Standard

µPD7759GC-3BH

Standard

Speech data ROM

(External)

5

5

DATA SHEET

1988, 1993

©

The mark 5 shows revised points.

Document No.

IC-2323A

(O.D.No.

IC-6960D)

Date Published

January 1993

Printed in Japan

The information in this document is subject to change without notice.