Zigbee ST(L4) Board (ZTU)

This ultra-low-power consumption development board comes with a ZTU Zigbee module and an STM32L431CC microcontroller (MCU) from STMicroelectronics. It can work with circuit modules or boards to help you prototype ideas and evaluate solutions.

Applications

• This development board applies to most custom solutions developed with the MCU SDK. You can use it to build Zigbee projects where the network modules communicate with the MCU through the serial protocol.
• 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 Zigbee-based control system works

Components

The development board is integrated with Tuya’s proprietary high-performance ZTU Zigbee module and STM32L431CC MCU from STMicroelectronics. It has onboard MCU reset buttons, LED, power port, and a USB-to-serial chip.

• For more information, see the ZTU Module Datasheet.
• For more information, see Zigbee General Solution.

I/O port and pin description

• 1: Micro-USB: Input 5V DC voltage and provide one extended serial port.

• 2: Button (RST): Reset the STM32L431CC MCU. Press the button to output low level signals.

• 3: LED indicator: Indicate the power state when the board is powered via the micro-USB connection.

• 4: Power selection jumper: Use a jumper cap to switch the power supply between the USB connection and external power supply.

• 5: USB to UART jumper: Use a jumper cap on PB11 and PB10 to connect to the USB-to-serial chip.

• 6: UART selection jumper: Use a jumper cap on PA2 and PA3 to connect the MCU to the ZTU module.

• 7: LED indicator: When PB1 outputs high, the LED is on.

• 8: External battery pin header: Connect a button cell to the positive (+) and negative (-) terminals for verifying low power mode.

  Pin description

  No.	Symbol	Description	Alternate functions
  1	NC	Leave it floating.	-
  2	NC	Leave it floating.	-
  3	RST	Reset the STM32L431CC MCU. Active low.	-
  4	3.3V	3.3V power pin.	-
  5	5V	5V power pin.	-
  6	GND	Ground pin.	-
  7	GND	Ground pin.	-
  8	NC	Leave it floating.	-
  9	PA0	I/O	TIM2_CH1, USART2_CTS, COMP1_OUT, SAI1_EXTCLK, TIM2_ETR, EVENTOUT，OPAMP1_VINP, COMP1_INM, ADC1_IN5, RTC_TAMP2, and WKUP1
  10	PA1	I/O	TIM2_CH2, I2C1_SMBA, SPI1_SCK, USART2_RTS_DE, TIM15_CH1N, EVENTOUT,OPAMP1_VINM, COMP1_INP, and ADC1_IN6
  11	PA4	I/O	SPI1_NSS, SPI3_NSS, USART2_CK, SAI1_FS_B, LPTIM2_OUT, EVENTOUT ,COMP1_INM, COMP2_INM, ADC1_IN9, and DAC1_OUT1
  12	PA5	I/O	TIM2_CH1, TIM2_ETR, SPI1_SCK, LPTIM2_ETR, EVENTOUT, COMP1_INM, COMP2_INM, ADC1_IN10, and DAC1_OUT2
  13	PA6	I/O	TIM1_BKIN, SPI1_MISO, COMP1_OUT, USART3_CTS, LPUART1_CTS, QUADSPI_BK1_IO3, TIM1_BKIN_COMP2, TIM16_CH1, EVENTOUT, and ADC1_IN11
  14	PA7	I/O	TIM1_CH1N, I2C3_SCL, SPI1_MOSI, QUADSPI_BK1_IO2, COMP2_OUT, EVENTOUT, and ADC1_IN12
  15	PA10	I/O	TIM1_CH3, I2C1_SDA, USART1_RX, SAI1_SD_A, and EVENTOUT
  16	PA9	I/O	TIM1_CH2, I2C1_SCL, USART1_TX, SAI1_FS_A, TIM15_BKIN, and EVENTOUT
  17	PB9	I/O	IR_OUT, I2C1_SDA, SPI2_NSS, CAN1_TX, SDMMC1_D5, SAI1_FS_A, and EVENTOUT
  18	PB8	I/O	IR_OUT, I2C1_SDA, SPI2_NSS, CAN1_TX, SDMMC1_D5, SAI1_FS_A, EVENTOUT
  19	PB5	I/O	LPTIM1_IN1, I2C1_SMBA, SPI1_MOSI, SPI3_MOSI, USART1_CK, TSC_G2_IO2, COMP2_OUT, SAI1_SD_B, TIM16_BKIN, and EVENTOUT
  20	PB1	I/O	TIM1_CH3N, USART3_RTS_DE, LPUART1_RTS_DE, QUADSPI_BK1_IO0, LPTIM2_IN1, EVENTOUT, COMP1_INM, and ADC1_IN16
  21	PB2	I/O	RTC_OUT, LPTIM1_OUT, I2C3_SMBA, EVENTOUT, and COMP1_INP
  22	PA8	I/O	MCO, TIM1_CH1, USART1_CK, SWPMI1_IO, SAI1_SCK_A, LPTIM2_OUT, and EVENTOUT
  23	PA11	I/O	TIM1_CH4, TIM1_BKIN2, SPI1_MISO, COMP1_OUT, USART1_CTS, CAN1_RX, TIM1_BKIN2_COMP1, and EVENTOUT
  24	PA12	I/O	TIM1_ETR, SPI1_MOSI, USART1_RTS_DE, CAN1_TX, and EVENTOUT
  25	PB12	I/O	TIM1_BKIN, TIM1_BKIN_COMP2, I2C2_SMBA, SPI2_NSS, USART3_CK, LPUART1_RTS_DE, TSC_G1_IO1, SWPMI1_IO, SAI1_FS_A, TIM15_BKIN, and EVENTOUT
  26	PB15	I/O	RTC_REFIN, TIM1_CH3N, SPI2_MOSI, TSC_G1_IO4, SWPMI1_SUSPEND, SAI1_SD_A, TIM15_CH2, and EVENTOUT
  27	PB14	I/O	TIM1_CH2N, I2C2_SDA, SPI2_MISO, USART3_RTS_DE, TSC_G1_IO3, SWPMI1_RX, SAI1_MCLK_A, TIM15_CH1, EVENTOUT
  28	PB13	I/O	TIM1_CH1N, I2C2_SCL, SPI2_SCK, USART3_CTS, LPUART1_CTS, TSC_G1_IO2, SWPMI1_TX, SAI1_SCK_A, TIM15_CH1N, and EVENTOUT
  29	GND	Ground pin.	-
  30	VCCA	Analog power pin.	-
  31	PB7	I/O	LPTIM1_IN2, I2C1_SDA, USART1_RX, TSC_G2_IO4, EVENTOUT, COMP2_INM, and PVD_IN
  32	PB6	I/O	LPTIM1_ETR, I2C1_SCL, USART1_TX, TSC_G2_IO3, SAI1_FS_B, TIM16_CH1N, EVENTOUT, and COMP2_INP

• STM32L431CC MCU debugging pins

  No.	Symbol	Description	Alternate functions
  1	GND	Ground pin.	-
  2	SWC	The JTAG debug port, SWCLK	PA14, LPTIM1_OUT, I2C1_SMBA, SWPMI1_RX, SAI1_FS_B, and EVENTOUT
  3	TRS	The JTAG debug port, NJTRST	PB4, I2C3_SDA, SPI1_MISO, SPI3_MISO, USART1_CTS, TSC_G2_IO1, SAI1_MCLK_B, EVENTOUT, and COMP2_INP
  4	SWD	The JTAG debug port, JTMS-SWDIO	PA13, IR_OUT, SWPMI1_TX, SAI1_SD_B, and EVENTOUT
  5	TDO	The JTAG debug port, JTDO-TRACESWO	PB3, TIM2_CH2, SPI1_SCK, SPI3_SCK, USART1_RTS_DE, SAI1_SCK_B, EVENTOUT, and COMP2_INM
  6	GND	Ground pin.	-
  7	TDI	The JTAG debug port, JTDI	PA15, TIM2_CH1, TIM2_ETR, USART2_RX, SPI1_NSS, SPI3_NSS, USART3_RTS_DE, TSC_G3_IO1, SWPMI1_SUSPEND, and EVENTOUT
  8	3.3V	3.3V power pin.	-

• ZTU module debugging pins

  No.	Symbol	Description	Alternate functions
  1	MTX	I/O	B7, Uart_RXD
  2	MRX	I/O	B1, Uart_TXD
  3	MRS	The reset pin. Active low.	-
  4	MSW	I/O	Used for firmware flashing
  5	GND	Ground pin.	-
  6	MVC	3.3V power pin on the module.	-

Load-carrying capacity

• When micro-USB inputs 5V DC voltage, the board can supply power to external components.

  Power pin	Rated voltage/maximum current
  VDD	5V/0.4A
  VCC	3.3V/0.4A

  The micro-USB input port is connected to a 5V/0.5A resettable fuse in series. The total supply current and output current of the development board cannot exceed 0.5A.

• Characteristics of the output voltage of 3.3V

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

  We tested the voltage under the condition that there is no output voltage on the micro-USB (CN1) terminal.

Schematic diagram and PCB

• The schematic diagram of the board:

  

• The PCB board:

  

Jumper settings

• The board has a built-in USB-to-serial chip. You can use a jumper cap on PB10 and PB11 to connect the MCU to the USB-to-serial chip.

  Pin connection description

  Silkscreen	P2	P3
  MCU pin	PB11	PB10
  USB-to-serial chip	USB-TXD	USB-RXD

• You can use a jumper cap on PA2 and PA3 to connect the MCU to the ZTU module.

  Pin connection description

  Silkscreen	P5	P7
  MCU pin	PA3	PA2
  ZTU module	TL_B1	TL_B7

• You can use a jumper cap to switch the power supply between the USB connection and external power supply. The following table provides the description of pin header P4.

  Silkscreen	Description
  BAT	Place a jumper cap on BAT and 3.3V to supply power via battery.
  3.3V	3.3V power output pin.
  USB	Place a jumper cap on USB and 3.3V to supply power via USB connection.

  The + and - pin headers are used to connect to a CR2450 battery.

Module connection for flashing

For flashing license and firmware, connect pins following the table and figure shown below.

USB-to-serial chip driver

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

• For Windows
• For Linux

Things to note

• The board has a built-in micro-USB port, so the additional power board is not necessary.
• If you connect the board to a power board, do not use the micro-USB port for voltage input.