Hi,
I'd like to activate the ALERT output of the TMAG5170, when new sensor data is available. I configured the sensor in this way:
SENSOR_CONFIG: 0x01C0
SYSTEM_CONFIG: 0x0000
ALERT_CONFIG: 0x2100
DEVICE_CONFIG: 5020
Where is my mistake in the configuration? I'm able to read the sensor data but I can't get any response of the ALERT-Pin. Do I have to use an Pull-Up or Pull-Down resistor?
Sebastian,
Welcome to E2E, thank you for reaching out with your question. The ALERT pin on TMAG5170 is open drain and does require a pull-up as shown here:
Additionally, your settings has ALERT_LATCH set to '1' while in active measure mode which will keep the device continually converting. When I check this setting on the EVM I see that the ALERT pin stays pulled high at all times. To change this, I can set ALERT_LATCH to '0', which will produce a single short low pulse on ALERT at the end of every conversion.
Alternatively, if I set the device to active trigger mode (with the trigger on SPI command bits) I am able to leave the ALERT_LATCH bit as '1'. This will keep the ALERT output high until I have read the output registers. This for me produces a longer signal on ALERT since the output will remain low until I am able to complete a read on the output.
Thanks,
Scott
