Epson Starts Shipping Samples of Audio Playback LSIs with Buzzer Sound Function, Flash Memory and Built-in Oscillation Circuit

- Enables audio playback functions to be easily added to existing products -

- TOKYO, Japan, October 3, 2023 -

Seiko Epson Corporation (TSE: 6724, "Epson") has developed and is now shipping samples of the S1V3F351 and S1V3F352 audio playback LSIs equipped with a buzzer sound function, flash memory for audio data and built-in oscillation circuit. Epson plans to produce 200,000 of these new LSIs per month.

Epson will exhibit these LSIs at CEATEC 2023 to be held in Makuhari Messe, Japan, from October 17 to 20, 2023.

S1V3F351 and S1V3F352 (Package Type: P-TQFP048-0707-0.50)

In addition to the growing popularity of water heater remote controls, home appliances and other devices equipped with audio functions, the use of audio alarms and guidance is also expanding in health equipment, office buildings and factories. Customers can easily embed audio playback functions into their existing products used to play that audio simply by connecting these LSIs to a serial interface.

To date, even higher priced speakers are used to equip audio playback functions to various devices because inexpensive, regular buzzers have not provided sufficient audio quality and acoustic pressure.

Epson has therefore developed these LSIs with audio and melody playback with a buzzer by using an originally-developed audio algorithm.

End users can set the audio to make it easy for them to hear it using a real-time audio speed and pitch adjustment function (S1V3F351 only). In addition, the 2-channel mixing functions make it possible to simultaneously play background music and audio, enabling customers to provide empathetic audio guidance.

The use of a high-compression and high-sound quality algorithm reduces the amount of memory needed to store audio data and makes it possible to install both multiple languages and a large library of background music. Epson also provides a voice creation PC tool that supports 12 languages and allows users to easily create multilingual voice data without requiring studio recording as a voice data development environment. Users can also use existing Waveform Audio File Format (WAV) data.

Epson will continue to help customers further improve the performance of their products and contribute to smart social infrastructure based on its philosophy of efficient, compact, precise innovation aimed at saving energy, saving space and delivering exceptional precision.

Product Features

1. Integrate a variety of audio playback functions

  1. Audio playback with electromagnetic buzzers and piezoelectric buzzers that can equip audio playback functions even into low-end products
  2. Voice speed and pitch conversion functions (adjustable in 5% steps between 75% and 125%) that enables each end user to adjust the audio as required
  3. 2-channel mixing audio playback (for playing background music + voice) that produces a sense of empathy
  4. Sampling rate of 15.625 kHz, which is high enough for background music as well as voice
  5. Equipped with a high-sound quality and high-compression algorithm that supports multiple languages and a large library of background music

2. Easily equip voice guidance functions into existing systems

  1. Simple host CPU serial interface
  2. Stand-alone mode that allows control without a host CPU or with only the GPIO of the host CPU

3. Easily create voice data with Epson's voice creation PC tool

  1. Studio recording is not needed; the PC tool is all that is needed to create voice data (support is provided for 12 languages)
    Americas: American English, American Spanish and Canadian French
    Europe: British English, German, French, Spanish, Italian and Russian
    Asia: Japanese, Chinese and Korean
  2. Voice guidance is enabled by transferring the voice number on the PC tool via the serial interface
  3. Audio data (WAV format) possessed by the user can be easily imported into the PC tool

4. Comes with an easy-to-use evaluation board

  1. Designed to easily connect to the host CPU
  2. Easily write voice data created by the customer
  3. Comes with a stand-alone control button that enables audio to be easily evaluated without the need for a host CPU connection
  4. Equipped with external QSPI-Flash

Related Links

Please see the website below for detailed product information.


Please see the website below to see a demonstration video for the Epson voice creation PC tool.


Please see the websites below for detailed CEATEC 2023 information.



Booth location: Key Device Area Hall 4 (Booth No. K018)

Online booth URL:

Product Specifications

Model No. S1V3F351 S1V3F352
Sound Flash Approx. 30 sec. Approx. 80 sec.
External QSPI-Flash I/F Supported (up to 16 MB)
Playback channels 2-channel mixing support (e.g., Ch.: 0 voice, Ch. 1: BGM)
Voice playback algorithm EOV (Epson original high-compression voice & high-quality sound format) /16-bit PCM
Sampling frequency 15.625kHz (ideal for background music as well)
Bit rate EOV: 16/24 kbps EOV: 16/24/32/40 kbps
Multiple sound ROM Supported
Gapless playback Supported
Volume adjustment Supported (0 db to -63.0 db:0.5 db step, silence)
Setting for number of repeats Supported (1 to 254 times; repeats until the stop command)
Voice speed conversion 75% to 125% (5% steps)
Pitch conversion 75% to 125% (5% steps) -
Tone generation Supported
Buzzer sound Supported
Recording and playback (with ADC for recording) Supported (uses external QSPI-Flash)
* Only 1 data supported
Host CPU interface SPI, UART, I2C, Standalone
Sleep & Deep Sleep modes Supported
Clock Internal oscillation / external oscillation
Operating voltage 1.8 V to 5.5 V
QSPI-Flash voltage Supported (3.3 V ±10%)
Flash programming voltage 2.2 V to 5.5 V 2.4 V to 5.5 V
Current consumption at
Deep Sleep mode (typ)
0.34µA 0.46µA
Package P-TQFP048-0707-0.50 (0.5mm pitch)

About Epson
Epson is a global technology leader whose philosophy of efficient, compact and precise innovation enriches lives and helps create a better world. The company is focused on solving societal issues through innovations in home and office printing, commercial and industrial printing, manufacturing, visual and lifestyle. Epson's goal is to become carbon negative and eliminate use of exhaustible underground resources such as oil and metal by 2050.
Led by the Japan-based Seiko Epson Corporation, the worldwide Epson Group generates annual sales of more than JPY 1 trillion.