ROHM Semiconductor LAPIS ML22Q2x4 Speech Synthesis LSI

ROHM Semiconductor LAPIS ML22Q2x4 Speech Synthesis LSI incorporates Flash for storing sound code data and can be controlled with a clock synchronization serial interface (ML22Q234), standalone interface (ML22Q244) or an I²C interface (ML22Q254). Integrating a D-class speaker amplifier in the ROHM Semiconductor LAPIS ML22Q2x4 makes the solution required for sound output possible with a single chip.

Features

Playback time
- ML22Q234, ML22Q254
  - 676Kbit - HQ-ADPCM playback of 33.8sec/16-bit straight PCM 6.88sec
  - 672Kbit - HQ-ADPCM playback of 33.6sec/16-bit straight PCM 6.72sec
- ML22Q244
  - 692Kbit - HQ-ADPCM playback of 34.6sec/16-bit straight PCM 6.92sec
  - 688Kbit - HQ-ADPCM playback of 34.4sec/16-bit straight PCM 6.88sec
- ML22Q274, ML22Q284, ML22Q294
  - 692Kbit - 4-bitADPCM2 playback of 27.6sec/16-bit PCM 6.9sec
Speech synthesis algorithm
- HQ-ADPCM (ML22Q234, ML22Q244, ML22Q254 only)
- 4-bit ADPCM2
- 8-bit non-linear PCM
- 8-bit/16-bit straight PCM (ML22Q234, ML22Q244, ML22Q254 only)
- 8-bit PCM, 16-bit PCM (ML22Q274, ML22Q284, ML22Q294 only)
- Can be specified for each phrase
Flash capacity
- 676 Kbit (30 phrases selection), 672 Kbit (62 phrases selection) (ML22Q234, ML22Q254)
- 692 Kbit (30 phrases selection), 688 Kbit (62 phrases selection) (ML22Q244, ML22Q274, ML22Q294)
- 692 Kbit (ML22Q284 only)
Sampling frequency (Fs)
- ML22Q234/ML22Q244/ML22Q254: 6.4kHz, 8.0kHz, 10.7kHz, 12.8kHz, 16.0kHz, 21.3kHz, 25.6kHz, 32.0kHz
- ML22Q274/ML22Q284/ML22Q294: 8.0kHz/16.0kHz/32.0kHz, 6.4kHz/12.8kHz/25.6kHz, or 10.7kHz/21.3kHz
- Can be specified for each phrase

Speaker driving amplifier is a D-class amplifier (driven by 8Ω)
CPU command interface
- ML22Q234/ML22Q274: Clock synchronization serial interface
- ML22Q244/ML22Q284: Standalone interface (built-in noise removal function)
- ML22Q254/ML22Q294: I²C interface (slave, maximum communication speed of 400kbps)
30 or 62 phrases are the maximum number of phrases (for all devices except ML22Q284, which is 30 phrases maximum)
Disconnection detection function
Speaker pin short detection function
Source oscillation frequency
- ML22Q234, ML22Q244, ML22Q254: 8.192MHz (typ.)(internal)
- ML22Q274, ML22Q284, ML22Q294: 4.096MHz (typ.)(internal)
2.0V to 5.5V power supply voltage
Flash memory access function by MCU (ML22Q234 and ML22Q254)
Flash memory is rewritable
- ML22Q234, ML22Q244, ML22Q254: 100 times
- ML22Q274, ML22Q284, ML22Q294: 80 times
Operating temperature range
- ML22Q234, ML22Q244, ML22Q254: –40°C to +85°C
- ML22Q274, ML22Q284, ML22Q294: –40°C to +105°C
ML22Q274, ML22Q284, and ML22Q294 devices are AEC-Q100 compliant

Applications

Automotive (ML22Q274, ML22Q284, ML22Q294 only)
- AVAS (Acoustic Vehicle Alerting System)
- Meter cluster
- Various warning sounds
Consumer
- Household appliances
- Housing equipment