STPM098C datasheet(43/110 Pages) STMICROELECTRONICS

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3.9

Overtemperature monitor (OTM)

STPM098C implements a monitoring unit of the average junction temperature able to detect excessive

overheating conditions affecting the device.

Figure 34. Temperature monitor ADC characteristics

Tj[º]

LSB=1.378Cº

257

Digital Code [LSB]

290

-66.52

Temperature measurement data is stored in a dedicated register and can be retrieved by PMBus™ readout of

Tj°C = 1.378°C×DTEMPREAD −66.52°C

(2)

Where:

DTEMPREADisthedigitalwordstoredinREAD_TEMPERATURE_2.

The digitized temperature information is compared by two hysteresis comparators with selectable threshold based

on the following scheme:

•

If DTEMP ≥ DTEMP_WR_TH occurs for an interval longer than T_otm_wr_flt, the OTM_WR flag is set. The

error flag remains set until the failure condition is removed.

•

If DTEMP ≥ DTEMP_SD_TH (= 175 deg.) occurs for an interval longer than T_otm_sd_flt, the OTM_SD

flag is set and SAFE_HIZ is established. The error flag remains set until the failure condition is removed

and a rinsing edge on VR1_EN or VR2_EN is detected.

Thermal warning thresholds can be independently configured by the following PMBus™ bit sets:

Table 35. Thermal warning configuration bits

OT_WARN_LIMIT1

OT_WARN_LIMIT0

Description

130 deg.

140 deg. (default)

150 deg.

160 deg.

STPM098C

Functional description

DS14440 - Rev 1

page 43/110

STPM098C Datasheet(PDF) 43 Page - STMicroelectronics