Select GPIO with current supply capability of 5 mA. Figure 8-10 shows that the SCL, SDA lines and INT pin can be shared. However, the function of the INT pin must be analyzed when shared by multiple sensors. As an example, if the sensors are configured to generate interrupt through the INT pin, the microcontroller needs to read all the sensors to determine which specific one sending the interrupt. Take the following steps sequentially to assign new I²C addresses to the four TMAG5173-Q1 shown in Figure 8-10:

• Turn on the GPIO#1 and wait until t_{start_power_up} time is elapsed.
• Address the device#1 with factory programmed address. Write to the I2C_ADDRESS register to assign a new address.
• Turn on the GPIO#2 and wait until t_{start_power_up} time is elapsed.
• Address the device#2 with factory programmed address. Write to the I2C_ADDRESS register to assign a new unique address.
• Turn on the GPIO#3 and wait until t_{start_power_up} time is elapsed.
• Address the device#3 with factory programmed address. Write to the I2C_ADDRESS register to assign a new unique address.
• Turn on the GPIO#4 and wait until t_{start_power_up} time is elapsed.
• Address the device#4 with factory programmed address. Write to the I2C_ADDRESS register to assign a new unique address.

Repeat the above steps if there is a power outage or power-up reset condition.

Figure 8-9 Power-Up Timing and I²C Address Allocation for the Four Sensors