T5AI-BOX Voice Solution

Tuya T5AI-BOX is a voice and screen multi-interaction AI box based on the T5-E1, an embedded Wi-Fi and Bluetooth combo module developed by Tuya Smart. Equipped with one microphone, one audio loopback, and one speaker, this AI box supports voice recognition and playback, offering voice interaction capabilities.

Features

• Module: T5-E1
  • ARMv8-M Star (M33F) @480 MHz
  • 16 KB ITCM and 16 KB DTCM
  • 8 MB SiP flash memory
  • 16 MB SiP PSRAM
  • 640 KB shared SRAM
• Audio: 2-channel 16-bit audio ADC, 1-channel 16-bit audio DAC, and a 4-band digital equalizer
• Screen: 1.54-inch SPI screen
• Wi-Fi:
  • IEEE 802.11b/g/n/ax compliant
  • 20 MHz and 40 MHz channel bandwidth
  • Support downlink multi-user multiple input, multiple output (DL MU-MIMO)
  • Integrated Bluetooth and Wi-Fi coexistence (packet traffic arbitration, PTA)
  • Support target wake time (TWT)
• Bluetooth:
  • Support Bluetooth Low Energy (LE) 5.4 standard
  • Transmit (TX) power of +6 dBm
  • Receive (RX) sensitivity of -97 dBm

Functional block diagram

Peripherals

Recommended I/O configuration of SPI LCD

LCD subscreen parameters

Things to note

Antenna clearance

• Do not use metal shells or plastic shells with metallic painting or coating in the direction of the antenna radiation. Do not use metal objects such as screws and rivets near the antenna, which might affect the antenna efficiency.
• Try to increase the distance from the top shell to the antenna to minimize the impact on antenna performance.
• Try to increase the distance from the upper and bottom shells to the antenna to minimize the impact on antenna performance.
• Keep the module away from speakers, power switches, cameras, HDMI, USB, and other high-speed signals to avoid interference.
• Avoid metal shielding near the antenna. If co-channel interference occurs, you must evaluate the impact on the antenna performance and ensure isolation from interference.

Antenna placement

• Horizontal placement
  We recommend that you place the module at the edge of the backplane with the antenna facing outward, and flush the module’s GND terminal with the backplane’s GND terminal. Both terminals are fully connected.
• Embedded placement
  Embed the module into the backplane through a slot that is flushed with or deeper than the module’s GND terminal. The side of the slot must be 15 mm or farther from the module’s board edge. A wider slot can achieve better performance, but is weaker than that of horizontal placement.
• Vertical placement
  Insert the module vertically into the backplane slot with the antenna facing upward. The module’s GND terminal and the backplane’s GND terminal must be fully connected. We recommend that you keep a clearance distance of 15 mm or more around the antenna.

Microphone and speaker

• Take an internal sound-proof measure between the microphone and speaker. Therefore, the speaker’s sound can be prevented from being directly transmitted to the microphone.
• The distance between the microphone pickup port and the speaker sound outlet must be ≥100 mm. The angle between the microphone pickup direction and the speaker sound projection direction should be ≥90°.
• The microphone is sealed with a silicone cover from a solid surface. This way, prevent direct hard contact between the silicone microphone and the structure, and reduce the casing vibration and sound transmission.

Flash firmware

• For firmware flashing, you need to connect 3.3V, GND, TX0, and RX0 pins.
• When a reset prompt appears, you need to power off and restart the device.

PCB layout

• Ensure power traces are short and wide, with minimal loops, and provide at least two 8 mil (inner diameter) vias or one 12 mil (inner diameter) via for main IC power pins.
• For power traces, use copper pours whenever possible and add sufficient ground vias for heat dissipation. Pay attention to the current-carrying capacity of single traces. Trace width reference (1 oz copper, outer layer): 20 mil width corresponds to 1A (without considering temperature rise).
• The power amplifier IC output lines require differential routing, with coupled traces fully ground-guarded. Trace width should be calculated based on peak output current, and routing should be kept as short as possible.
• The module’s audio output signals AUDLP and AUDLN must be routed as differential pairs and fully ground-guarded.
• The microphone signals must be routed as differential pairs and fully ground-guarded, with a minimum trace width of 8 mil.

Reference

• Schematic diagram of the AI box
• T5-E1 design guidelines