AVS VWRK4 user manual

Product overview

Tuya AVS voice module VWRK4 is based on ARM 4-Core 64 bit A35 rockchip 3308 MCU. The MCU is integrated voice wake & noise cancellation algorithm. The module can be integrated into the IoT device/gateway/smart speaker. The MCU RK3308’s frequency is 1.3GHz, which can provide powerful computing ability. And also the RF chip RTL8723DS contains WiFi Sing-band 1X1+Bluetooth v2.1+ EDR/ Bluetooth 3.0/3.0+HS/4.2. This ability make it easy to connect to the Tuya IoT platform.

Features

• ARM 4-Core 64 bit A35 rockchip 3308 MCU

• 1.3GHz frequency

• Work voltage: 3.3-5.5V（5V default）

• peripherals：2Uart，7ADC，RGB666，1SPI，1I2C，2*USB

• Antenna：ipex/on-board antenna

• Sampling rate:16K/16bit

• Mic feature

  • 4-way mic pickup, stereo playback.
  • 6-way mic pickup, single-channel playback.
  • others

• Audio output: stereo HPOUT and stereo LINEOUT

• Audio AUX IN: support

• Recommend distance: <=5m

• Entertainment：

  • Approved：amazon music, audible, iHeartRadio, TuneIn
  • Not requested: apple music, Deezer, dHits, Gaana, Gimme Radio, Pandora, Spotify, Saavn, SiriusXM, Uta Pass.

• Skill：all the skill contains in Alexa. For example:

  Newest arrivals, Business & finance, Connected car, Education & Reference, Food &drink, Game & trivia, Health & fitness, kids, lifestyle, local, Movies & tv, Music & Audio, News, Novelty & humor, productivity, shopping, Smart home, sports, Travel & transportation, Utilities, Weather.

  

Hardware feature

• Circuit diagram of VWRK4 voice kit

  

  The voice kit VWRK4 is based on rockchip 3308 platform. There are some peripheral interfaces, for example, 4 mic, speaker, 3.5mm headphone interface, 4 buttons, 12 RGB LED. HOST is used for the external storage devices. OTG is used for system platform debug. The RF contains WIFI/BLE/Zigbee. The Zigbee module is tuya’s TYZS5 module. The antenna of WIFI/BLE is an external 2.4G Ipex antenna. The reset button is a software reset solution. The voice kit supply voltage is 5V （both the two USB interfaces are OK）

• The picture of voice kit VWRK4

  

Design instruction

• MIC circuit

  

  MIC1/2/3/4 circuit uses the MICPN5/6/7/8 channel of the RK3308 platform. you can choose 200-20KHZ voice signal. Using differential traces to reduce interference during PCB layout.

  

• Voice control circuit

  

  The audio button control circuit uses two buttons and a resistor divider scheme. It determines which button is pressed by ADC sampling and then performs related functions.

• Headphone circuit

  

  The earphone support 3.5mm earphone. The mic of earphones can be used to communicate.

• USB circuit

  

  The circuit of USB contains a 5V supply power of EVB board. The USB circuit can use to debug and external interface functions. The interface of USB OTG can identify OTG device through the USB_OTG_ID signal. You can use this port for ADB loading and debugging. The USB Host can connect an external storage device, etc.

• LED circuit

  The LED circuit module use 12 RGB LED. The LED controls the AW20036 chip through I2C protocol. Through the configuration, the register can control any channel of light.

  

• ZigBee circuit

  The Zigbee circuit uses the external tuya TYZS5 module. TYZS5 module’s data transmission is through serial ports. Its power can be powered by 5V to 3.3V LDO. The design of Zigbee’s antenna should leave the headroom. The distance between the antenna and other metal should over 15mm. This method can avoid excessive signal attenuation.

  

• Peripheral interface

  The 2.54mm pin header can be used to expand some peripheral. Including LCD module (LCD_x signal, multiplexable IO), Zigbee port (AP_x), debug port (UNO_TX/RX).

  

• Reset circuit

  The reset circuit use button for soft reset. We reset the system by pulling down the reset signal of rockchip 3308.

  

Application area

The relation between Alexa built-in and work with Alexa:

App instruction

• You should let your device or voice kit for Alexa (RK3308) connect to the internet through the Tuya smart app. You should let your device through the amazon authorization use your amazon account. You can use this app to add the Zigbee/IR device if your device integrates those abilities.

  

• Amazon account link through the Tuya Smart app. Then you can control the smart device through voice control
  

Size

VWRK4 has 4 rows of pins with a pin pitch of 1.5mm

VWRK4 size：35mm（W）*35mm（L）*3.2mm（H）

Interface definition

VWRK4 need external mic and speaker complete the interaction.

Parameter

Absolute electrical parameter

Work condition

Transmit power

WIFI transmit power

BLE transmit power

Receive power

WIFI receive power

BLE receive power

RF characteristics

Basic RF characteristics

Output power

TX continuous transmit power,VBAT=5V

WIFI transmit power

BLE transmit power

Receive sensitivity

RX sensitivity,VBAT=5V

WIFI receive sensitivity

BLE receive sensitivity

Antenna

Antenna type

VWRK4 uses the onboard IPEX connector to connect with the external FPC antenna by default. Users can also design PDB antennas to extend the baseboard through the module ANT interface to meet the needs of specific products.

Reduce antenna interference

For the optimal performance. Some suggestions to the users:

• The distance between the module antenna and other metal parts must be at least 15mm.

• Option 1 and 2 is the best way. The RF parameter is almost the same with the signal module

• Option 3 will lose some RF performance, attenuating by 1-2 dBm.

• Option 4 is not recommended. The RF signal will be significantly attenuated.
  

Appendix: Statement

Federal Communications Commission (FCC) Declaration of Conformity

FCC Caution: Any changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to operate this equipment.

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

Note: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.

• Increase the separation between the equipment and receiver.

• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.

• Consult the dealer or an experienced radio/TV technician for help.

Radiation Exposure Statement

This equipment complies with FCC radiation exposure limits set forth for an uncontrolled rolled environment. This equipment should be installed and operated with a minimum distance of 20cm between the radiator and your body.

Important Note

This radio module must not be installed to co-locate and operating simultaneously with other radios in the host system except in accordance with FCC multi-transmitter product procedures. Additional testing and equipment authorization may be required to operate simultaneously with other radio.

The availability of some specific channels and/or operational frequency bands are country dependent and are firmware programmed at the factory to match the intended destination. The firmware setting is not accessible by the end-user.

The host product manufacturer is responsible for compliance to any other FCC rules that apply to the host not covered by the modular transmitter grant of certification. The final host product still requires Part 15 Subpart B compliance testing with the modular transmitter installed.

The end-user manual shall include all required regulatory information/warning as shown in this manual, including: This product must be installed and operated with a minimum distance of 20 cm between the radiator and user body.

This device has got an FCC ID：2ANDL-VWRK4. The final end product must be labeled in a visible area with the following: “Contains Transmitter Module FCC ID:2ANDL-VWRK4”

This device is intended only for OEM integrators under the following conditions:

• The antenna must be installed such that 20cm is maintained between the antenna and users, and

• The transmitter module may not be co-located with any other transmitter or antenna.

As long as the 2 conditions above are met, further transmitter tests will not be required. However, the OEM integrator is still responsible for testing their end-product for any additional compliance requirements required with this module installed.

Declaration of Conformity European notice

Hereby, Hangzhou Tuya Information Technology Co., Ltd declares that this module product is in compliance with essential requirements and other relevant provisions of Directive 2014/53/EU,2011/65/EU.A copy of the Declaration of conformity can be found at https://www.tuya.com

with the EU directive for waste electrical and electronic equipment (WEEE- 2012/19/EU). Instead，it should be disposed of by returning it to the point of sale, or to a municipal recycling collection point.