4 Application information

STw4141

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3.5

Thermal shutdown protection

Thermal shutdown protects the device against damage due to overheating when maximum

operating junction temperature is exceeded. The device is kept in reset until junction

temperature decreases by 25°C approximately.

4

Application information

4.1

User mode details

The following table describes the different user modes available. Depending on the application

constraints (processor I/O pins available) and expected efficiency, PWM or PFM mode are

forced or automatically controlled by STw4141 internal digital gates.

Table 7.

STw4141 available user modes

Mode

User mode / pins

EN

AUTO

MODE/

SYNC

OFF

Shutdown

L

X

X

FORCED

Forced PFM

H

L

L

Forced PWM

H

L

H

Forced PWM and synchronized external clock

H

L

CLK

AUTO

Auto mode

H

H

L

Forced PWM

H

H

H

Forced PWM and synchronized external clock

H

H

CLK

Table 8.

Operating mode information (STATE pin - digital output)

Operation mode

State pin voltage level

PFM

VOUT1

PWM

GND