Bluetooth SoC Board V2 (BTU)

Last Updated on : 2024-06-18 10:32:48download

The Tuya Sandwich Bluetooth SoC board V2 (BTU) has Tuya’s BTU Bluetooth Low Energy (LE) network module as a microcontroller, which is designed to help you easily prototype your IoT ideas. It can work with other circuit boards to implement specific features.

Scenarios

This development board applies to a wide range of prototypes implemented with Tuya’s no-code or TuyaOS solutions.
Develop with the board to build your IoT projects easily and fast.
You can use this board for different development purposes.
- Embedded program development and debugging
- App development and debugging
- Creating connected devices that can be controlled with a mobile phone
- Getting started with IoT development and learning how the Bluetooth-based control system works

Components

The development board is integrated with Tuya’s proprietary high-performance BTU Bluetooth module. The development board has on-board buttons, GPIOs, and a USB-to-serial chip. For more information, see the BTU Module Datasheet.

I/O port functions

Bluetooth SoC Board V2 (BTU)

Jumper switches (P9 and P8), used to change the mode of the user port. Placing a jumper cap on PB1-TXD and PB7-RXD enables the module’s pin to connect to the TX and RX pins. Placing a jumper cap on PB1-U_RXD and PB7-U_TXD enables the module’s pins to connect to the U2 chip so that the user port can communicate with the module through the micro-USB port.
Micro-USB (P2): Provides 5V DC voltage or acts as a serial port.
DC-005 (P1): Provides 12V DC voltage.
Button (S2): Connected to the PA0 pin on the module. When the button is pressed, a low level is output. When the button is released, a high level is output.
Serial port (P3): Used to flash firmware to the BTU module.
Button (S1): Connected to the RST pin on the module. When the button is pressed, a low level is output, with the module being reset.

Pin description

No.	Symbol	Description
1	NC	Leave it floating.
2	NC	Leave it floating.
3	RST	Reset the module at a low level.
4	3V3	3.3V power pin.
5	5V	5V power pin.
6	GND	Ground pin.
7	GND	Ground pin.
8	VIN	12V power pin.
9	PB6	`GPIOB_6` of the module, which can be reused as the ADC.
10	NC	Leave it floating.
11	NC	Leave it floating.
12	NC	Leave it floating.
13	NC	Leave it floating.
14	NC	Leave it floating.
15	TX	Use a jumper cap to switch to the `GPIOB_1` pin of the module. This pin can be reused as the TXD of the user port.
16	RX	Use a jumper cap to switch to the `GPIOB_7` pin of the module. This pin can be reused as the RXD of the user port.
17	PA1	`GPIOA_1` of the module.
18	PC2	`GPIOC_2` of the module, which can be reused as the PWM.
19	PD3	`GPIOD_3` of the module.
20	PC3	`GPIOC_3` of the module, which can be reused as the PWM.
21	PB4	`GPIOB_4` of the module, which can be reused as the PWM.
22	PD4	`GPIOD_4` of the module.
23	PA7	`GPIOA_7` of the module. It defaults to the SWS pin, used for firmware flashing.
24	PB5	`GPIOB_5` of the module, which can be reused as the PWM.
25	PC4	`GPIOC_4` of the module, which can be reused as the ADC.
26	PD2	`GPIOD_2` of the module, which can be reused as the PWM.
27	PA0	`GPIOA_0` of the module.
28	PD7	`GPIOD_7` of the module.
29	GND	Ground pin.
30	NC	Leave it floating.
31	PC0	`GPIOC_0` of the module.
32	PC1	`GPIOC_1` of the module.

Load-carrying capacity

When DC-005 inputs 12V DC voltage, the board can supply power to external components.

Power pin Rated voltage/current

VIN Depends on the input current of the adapter connected to the DC-005 terminal.

5V 5V/1A

3V3 3.3V/0.6A

This board outputs rated power of 5W, which cannot support the long-time simultaneous output of 5V/1A and 3.3V/0.6A.
Characteristics of the output voltage of 5V

Output current 0A 0.25A 0.5A 0.75A 1A 1.25A

Output voltage 5.01V 5.00V 4.99V 4.98V 4.98V 4.97V

We tested the voltage under the condition that there is no output voltage on the 3V3 pin.
Characteristics of the output voltage of 3V3 pin

Output current 0A 0.15A 0.3A 0.45A 0.6A 0.75A

Output voltage 3.34V 3.36V 3.37V 3.37V 3.38V 3.38V

We tested the voltage under the condition that there is no output voltage on the 5V pin.

Power pin	Rated voltage/current
VIN	Depends on the input current of the adapter connected to the DC-005 terminal.
5V	5V/1A
3V3	3.3V/0.6A

Output current	0A	0.25A	0.5A	0.75A	1A	1.25A
Output voltage	5.01V	5.00V	4.99V	4.98V	4.98V	4.97V

Output current	0A	0.15A	0.3A	0.45A	0.6A	0.75A
Output voltage	3.34V	3.36V	3.37V	3.37V	3.38V	3.38V

Schematic diagram and PCB

The schematic diagram of the board:

The PCB board:

Bluetooth SoC Board V2 (BTU)

How USB-to-TTL works

The board has a built-in USB-to-serial chip. The single-channel USB port can provide one extended serial port. You can use a jumper cap to allow the user port on the module to connect to the USB-to-serial chip.

Pin connection description

Silkscreen P9 P8

Module PB1 PB7

Pins on board TX RX

USB-to-serial chip USB-RXD USB-TXD
The serial port is left floating and not connected to the pins on the USB-to-serial chip or the board. The two headers are open without jumper caps.
The serial ports on the module are connected to the USB-to-serial chip. The TX and RX on the board are left floating. Put the jumper caps as shown below.
The serial ports on the module are connected to the pins on the board. The pins on the USB-to-serial chip are left floating. Put the jumper caps as shown below.

Silkscreen	P9	P8
Module	PB1	PB7
Pins on board	TX	RX
USB-to-serial chip	USB-RXD	USB-TXD

USB-to-TTL chip driver

Download the USB-to-TTL chip driver for your operating system.

Things to note

The board has a built-in power supply port and circuit, so the additional power board is not necessary.