LP87702-Q1: Thermal warning - set/clear interrupt

Michal Kusmirek

Part Number: LP87702-Q1

Hi,

LP87702-q1 has two selectable thresholds (125degC and 140degC) for thermal warning.

If threshold = 140degC and PMIC reach 140degC, interrupt occur on nINT pin (logic 0).

What temperature will clear this interrupt (thermal warning) (adequate registers) ?

And the same question for threshold 125degC. What PMIC temperature will clear thermal warning registers?

Best regards

over 3 years ago

0 Samuli Piispanen over 3 years ago

TI__Expert 4355 points

Hi Michal,

TDIE_WARN_INT is latched bit and it will require manual clearing. The interrupt will not clear itself if the temperature drops below the threshold. It can be cleared by writing 1 to it if the temperature is below the threshold.

For real time status of the thermal warning you can use I2C to poll the TDIE_WARN_STAT bit.

Best regards,

Samuli Piispanen

0 Michal Kusmirek over 3 years ago in reply to Samuli Piispanen

Prodigy 40 points

Hi Samuli,

How we can control PMIC temperature? TDIE_WARN_STAT can be read by i2c and this register is depended on PMIC temperature. am I right?
If so, for which temperature this register change state? (for 140 and 125 threshold)

Best regards
MK

0 Samuli Piispanen over 3 years ago in reply to Michal Kusmirek

TI__Expert 4355 points

Hi Michal,

Yes, TDIE_WARN_STAT value depends on the PMIC temperature and TDIE_WARN_LEVEL setting. The temperature where TDIE_WARN_STAT goes 1 is configured with TDIE_WARN_LEVEL bit.

Also note that there is 20C hysteresis in the thermal warning as well as some tolerance in the warning level.

Best regards,

Samuli Piispanen

0 Michal Kusmirek over 3 years ago in reply to Samuli Piispanen

Prodigy 40 points

Yes, I know it.
For threshold 140C, and temperature falling down from 140C or above to 120C, TDIE_WARN_STAT change state for 130C or lower value?

I mean for thermal warning threshold = 140C, when temperature rising, and exceed 140C TDIE_WARN_STAT register change state from "0" to "1".
If temperature fall down from 140C below 130C, TDIE_WARN_STAT register change state from "1" to "0".
Am I right?

Best regards
MK

+1 Samuli Piispanen over 3 years ago in reply to Michal Kusmirek

TI__Expert 4355 points

Hi Michal,

Hysteresis is 20C. TDIE_WARN_STAT will change state from 1 to 0 when the die temperature drops 20C below the set TDIE_WARN_LEVEL.

In other words, with 140C setting (not taking the tolerance into account)

0 to 1 change will happen at 140C.
1 to 0 change will happen at 120C

Best regards,

Samuli Piispanen

Power management

Power management forum

LP87702-Q1: Thermal warning - set/clear interrupt