IPS1025H datasheet(12/32 Pages) STMICROELECTRONICS

12 / 32 page

Protections and diagnostic

The IC integrates several protections to help the design of robust applications.

7.1

Under-voltage lock-out

The IC is turned off if the voltage on VCC pin falls below the turn-off threshold (VUVOFF). Normal operation restarts

after VCC exceeds the turn-on threshold (VUVON). Turn-on and turn-off thresholds are defined in Table 4.

7.2

Over-temperature

The device is protected against overheating in case of overload conditions. During the driving period (when the

MCU is forcing the IN pin high), if the output is overloaded, the device suffers two different thermal stresses: one

related to the junction temperature of each output channel, and the other related to the whole case temperature.

The two thermal faults (Thermal Junction and Thermal Case) have different trigger thresholds: TJSD and TCSD,

respectively.

Usually, in thermal stress conditions due to overload, the junction thermal shutdown is the first protection that is

activated: the output channel (OUT) is turned off when its junction temperature (TJ) is higher than the activation

threshold (TJSD) and turned back on when it falls below the reset threshold (TJR). This behavior continues while

overload on the output persists. When the thermal protection is active, the FLT1 (current source) becomes active

accordingly.

If the thermal protection is active and the temperature of the case (TC) increases over the case protection

threshold (TCSD), then the thermal case protection is activated and the output is switched off until the junction

temperature and case temperature fall below their respective reset thresholds (TCR and TJR). The FLT1 pin is

active even when thermal case events occur.

Figure 7 shows the thermal protection behavior, while Figure 8 shows typical temperature trends and output vs.

input state.

IPS1025H, IPS1025H-32, IPS1025HQ, IPS1025HQ-32

Protections and diagnostic

DS13780 - Rev 3

page 12/32

IPS1025H датащи(PDF) 12 Page - STMicroelectronics