About TMP461

Hi Nat,

Sorry for the confusion! The THERM pin trips when the measured temperature result is higher than the THERM limit register (0x19 or 0x20), and THERM pin untrips when the measured temperature result is below the difference of (THERM limit register -  THERM Hysteresis register). The THERM limit – hysteresis is the temperature setting for the THERM pin.

For example, let’s say THERM limit register sets to 110°C, and the result temperature is 116°C then the THERM pin will trip. If hysteresis register is set to 10°C then the THERM pin will untrip when the temperature result goes below 100°C.

You are absolutely correct that there is a small delay between each point of the measured temperature. Why the THERM pin didn’t trip at 110°C but instead of 116°C. The circles on the measured temperature line in the graphs indicate when the temperature conversion ends. Since the THERM and ALERT limits are compared with the temperature result at the end of the conversion and not simultaneously, the THERM and ALERT flags and pins will also trip and untrip at the end of the conversion. This is why you see a small delay.

Hope this helps with the explanation.

Aaron

Dear Aaron
Thank you for your reply.

And one more question:
What the delay time between each point of the measured temperature?

Thanks

BRS
Nat

Hi Nat,

I wouldn't call that is a delay time. As I mentioned on the previous posted, the temperature comparison didn't happen until at the end of the ADC conversion time is completed. For example, the THERM hysteresis is set 110°C by the time the temperature register (0x00 or 0x01) is read, the temperature result is already reached to a higher temperature. That is why the graph indicated that the measured temperature at 116°C, and the THERM pin trip at that moment.

The typical of conversion time for both local and remote is 15ms. Please refer to EC table if you need more detail.

Hope this helps!

Aaron

Dear Aaron
Thank you for your reply.

One question, the temperature in my room is 29,
I set high temp limit register (0x0B) to 45(0x2D)

I used hair dryer then temperature more then 45, alert happen and led become to red.
I used fan then temperature low then 25, but the led still red, no become to green

Do you know what’s happen?
Any control fault?

BRS
Nat

Hi Nat,

I'll get back to you.

Aaron