Evaluation board



External Parts



  • Q1Supply voltage.
  • ASingle power supply : 2.2V ~ 5.5
  • Q2Recommended Operating temperature.
  • A-40℃~85℃
  • Q3Supported Host Interface.
  • A- Synchronous Serial Interface
    - Asynchronous serial interface (UART)
    (Supported only when system clock is 32.768 kHz.)
    - I2C interface
  • Q4System Clock specification?
  • A- Frequency (direct input): 32.768 kHz or 12.288 MHz
    - Frequency (oscillator): 32.768 kHz
  • Q5Package specification.
  • A52-pin QFP (10 mm x 10 mm) with 0.65 mm pitch-pins
  • Q6Audio format?
  • AEPSON original Voice format: eov, sampling frequency is 16kHz(fixed), the bitrate can be selected by 16/24/32/40kbps.
  • Q7How different EOV and ADPCM?
  • AEOV(16kHz) can provide better sound quality and small memory size comparison with ADPCM. the data size is 1/3-1/4 comapriosn with ADPCM16kHz, 2/3-1/2 comparison with ADPCM 8kHz.
  • Q8How many minutes voice can be put on SPI-Flash?
  • APlease refer following table.(the time is estimates on default, it is related with speech data)
    SPI-Flash size EPSON(16kHz) ADPCM(16kHz) ADPCM(8kHz)
    1MB 8min+ 2min+ 4min+
    2MB 16min+ 4min+ 8min+
    4MB 33mini+ 8min+ 16min+
    8MB 1hour 6min+ 16min+ 33min+
    16MB 2hour 13min+ 33min+ 1hour 6min+
  • Q9Max SPI-Flash size for S1V3G340.
  • A16MB
  • Q10AMP included?
  • ANo.
  • Q11SPI-Flash is mandatory?
  • ANo, if host can send voice data(streaming mode), no need to use. Streaming mode is supported on Host CPU mode:SPI.
  • Q12If not use SPI-Flash, how to set pins for SPI-Flash?
  • AInput pin SMSI:Low, another Output Pins:Open.
  • Q13What is GPO pins?
  • AHost CPU can set GPO pins High or Low.
    Please use if host CPU does NOT have enough GPIO.
    S1V3G340 has 7 GPO pins.
  • Q14S1V3G340 supports Standby mode?
  • AYes, standby in/out can be controlled by command and pin control.
  • Q15What does that mean "sequencer"?
  • AThe sequence function can connect the phrases. Below example connects 3 phrases. S1V3G340 can connect up to 64. ex) "Current" "temperature setting is" "25degree".
  • Q16The delay between phrases in sequencer function is possible?
  • AYes, S1V3G340 supports 0ms or 20-2047ms(1ms step).

Evaluation board

  • Q1Evaluation Board is available?
  • AYes.
    Once customer can get the evaluation board and voice data creation tool, customer can out the sound soon.
    Please contact our distributor or sales.
  • Q2What is the fist step after getting evaluation board?
  • APlease register following by the sheet including evaluation board. EPSON provides following information.
    • ID, passwrod to access evaluation board download site include document, tool etc.
    • voice data creation tool
    • license file for speech data creation tool
    • KEYCODE for a customer
  • Q3What is KEYCODE?
  • AID character for a customer structured by alphabet and number EPSON provides. It is nesessary to set both voice data creation tool and LSI.
  • Q4The evaluation board can connect with HOST CPU board?
  • AEvaluation board has the holes for HOST CPU connect.
  • Q5The evaluation board can connect with extrenal amp?
  • AYes, evaluation board has a hole for connect.
  • Q6The evaluation board can be used as mass production?
  • ANo, the board is just for evaluation.
  • Q7Anything need to prepare to use the evaluation board?
  • APlease prepare following.(require FTDI driver)
    • mini USB cable
    • speaker
    • PC for tools(listed on evaluation board download site)
  • Q8Evaluation board cuicuit is listed?
  • AYes, it's included in evaluation board simple manual.(listed on evaluation board download site)
  • Q9Evaluation board BOM is listed?
  • AYes, it's included in evaluation board simple manual.(listed on evaluation board download site)


  • Q1SPI-Flash data can be updated through S1V3G340 from Host CPU?
  • AYes.(*Host Interface mode should be SPI)
  • Q2How to write data onto SPI-Flash?
  • APlease refer following manuual.
    • S1V3G340,S1V3S344 On board Flash data update
    • Flash access specification
    • (listed on evaluation board download site)
  • Q3What output data from voice data creation tool should be written on SPI-Flash
  • AROMImage_xxxxxx.bin
  • Q4Requirement Clock precision?
  • A±50ppm
  • Q5Possible to stream voice data from Host CPU on UART mode?
  • ANo, becase of bitrate is NOT enough.


  • Q1How to set KEYCODE to LSI?
  • ACommand : ISC_TEST_REQ
  • Q2What is MSGRDY pin?
  • AThis pin is used for informing ready to send RESP or IND message from S1V3G340 to Host CPU.
  • Q3S1V3G340 has volume setting function?
  • AYes, by following command, a volume can be set.
    • ISC_AUDIO_CONFIG_REQ (absolute value set)
    • ISC_AUDIO_VOLUME_REQ (increase/decrease set)
    It might be saturated by increasing a volume, please evaluate before fix.
  • Q4S1V3G340 has repeat function?
  • AYes, it can be sent on command.
  • Q5Message protocol manual does not reccommend sequence playback on I2C mode, any issue?
  • AI2C transfer rate is not so fast.
  • Q6What data should be sent on streaming mode?
  • APlease send EOV file(*.eov), EOV file is generated under "project_name/sound\eov" generated from voice data creation tool.
  • Q7Volume setting can be changed on stream playing?
  • APlease set between ISC_AUDIODEC_READY_IND and next ISC_AUDIODEC_DECODE_REQ, it takes some time to change output volume.
  • Q8It is NOT neccesarry a final streaming is 512/1024/2048byte?
  • AYes.

External Parts

  • Q1Any recommend AMP?
    - IS31AP4991
    -NJU7084(on evaluation baord)
  • Q2Any recommend SPI-Flash?
  • A


    • IS25LP128
    • IS25LP064
    • IS25LP032
    • IS25LP016


    • S25FL127S (128Mbit SPI, SOIC8)
    • S25FL164K (64Mbit SPI, SOIC8)
    • S25FL132K (32Mbit SPI, SOIC8)
    • S25FL116K (16Mbit SPI, SOIC8)


    • S25FL032P: 32Mbit
    • S25FL208K: 8Mbit


    • MX25L6406EM2I (on evaluation board)

    Please check SPI-Flash interface specification, command, supply voltage specification.

  • Q3SPI-Flash written by ROM writer can be used?
  • AYes, please write from address 0.


  • Q1Cannot communicate.
  • APlease check message protocol manual chapter 3.
    • padding word(0x00), message start command(chapter3.2)
    • check MSB/LSB on sending command(chapter 3.3)
    • check I2S slave ID(0110110) (chapter 3.3.3)
  • Q2NO sound is out.
  • A
    • Check KEYCODE is set on voice data creation tool.
    • Check KEYCODE is set to LSI by ISC_TEST_REQ command.
    • Check KEYCODE MSB/LSB on ISC_TEST_REQ command.
  • Q3It takes some time to change volume after sending volume change command.
  • AS1V3G340 has smooth control to avoid click noise by big gain change, by this function it takes a time.

    Please set below tsc rime after sending volume change command, and then send voice start command.

    time for smooth control function (tsc)
    tsc = 166.4 * | A - B | [ms]
    A : 10 ^ ( Gstart/20 ) ; Gstart : current gain[dB]
    B : 10 ^ ( Gend/20 ); Gend : new gain[dB]

    ex) current gain: 0dB, new gain:6dB case,tsc = 165.6 msec.

    * Also after mute release, smooth control is available, please set tsc time after mute release and then send voice start command.

  • Q4How to reduce white noise.
  • Awe recommend below(1), (2)

    (1) voice data gain up and speaker AMP gain down

    By voice data gain up and speaker amp gain down, white noise can be decreased. Please follow below.

    1. voice data gain up

      Please go to ESPER2 menu "Tool" ---> "Sound Setting".
      Please change the number by "Volume" slider to 130(default:100), by changing volume from 100 to 130, output voice data gain is increased 6db.

    2. AMP gain down

      Please down amp gain 6db
      * Please evaluate output data is saturated or not.

    (2) Avoid voltage fluctuation

    D class CMP on S1V3G340 is quite sensitive against voltage fluctuation, so voltage fluctuation cause white noise.
    especially on voice playback, voltage fluctuation is apt to occur.
    Please refer following.

    • Put more than 10uF electrolytic capacitor to HVDD.
    • Put more than 0.1uF ceramic capacitor around HVDDs.
  • Q5Once stop the voice output by ISC_SEQUENCER_STOP_REQ command, there is a case voice data is NOT out.
  • AWe announce this, please refer " S1V3033*, S1V3034*, S1V3S344, S1V3G340 Specification Restriction for stop message during playback" file. (listed on evaluation board download site)
  • Q6Output voice data is cut on streaming playback.(Host interfacebmode:SPI)
  • AIt might be not enough the streaming data rate, please send streaming data soon after receiving ISC_AUDIODEC_READY_IND or increase the transfer rate.

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