STCN75DS2F datasheet(12/35 Pages) STMICROELECTRONICS

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Operation

STCN75

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2.3

Comparator mode

In Comparator mode, each time a temperature-to-digital (T-to-D) conversion occurs, the new

digital temperature is compared to the value stored in the TOS and THYS registers. If a fault

tolerance number of consecutive temperature measurements are greater than the value

stored in the TOS register, the OS/INT output will be asserted.

For example, if the FT1 and FT0 Bits are equal to “10” (fault tolerance = 4), four consecutive

temperature measurements must exceed TOS to activate the OS/INT output. Once the

OS/INT output is active, it will remain active until the first time the measured temperature

drops below the temperature stored in the THYS register, whereupon it will reset to its

inactive state.

Putting the device into Shutdown mode does not clear OS/INT in Comparator mode.

2.4

Interrupt mode

In Interrupt mode, the OS/INT output becomes active when the measured temperature

exceeds the TOS value a consecutive number of times as determined by the Fault Tolerance

bits (FT1, FT0) value in the Configuration register. Once activated, the OS/INT can only be

cleared by reading from any register (temperature, configuration, TOS, or THYS) on the

device. Once the OS/INT has been deactivated, it will only be reactivated when the

measured temperature falls below the THYS value a consecutive number of times equal to

the FT value. This mode is better suited for interrupt driven microprocessor based systems.

STCN75DS2F Datasheet(PDF) 12 Page - STMicroelectronics