DS75

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comparison is equal to the conversion resolution set by the R1 and R0 bits in the configuration register.

comparator.

The active state of the O.S. output can be changed via the POL bit in the configuration register. The

power-up default is active low.

If the user does not wish to use the thermostat capabilities of the DS75, the O.S. output should be left

storage of system data.

Comparator Mode — When the thermostat is in comparator mode, O.S. can be programmed to operate

with any amount of hysteresis. The O.S. output becomes active when the measured temperature exceeds

configuration register. O.S. then stays active until the first time the temperature falls below the value

Thermostat comparator mode operation with FT = 2 is illustrated in Figure 4.

Interrupt Mode — In interrupt mode, the O.S. output first becomes active when the measured

configuration register. Once activated, O.S. can only be cleared by either putting the DS75 into shutdown

O.S. has been deactivated, it will only be reactivated when the measured temperature falls below the

putting the device into shutdown mode or reading any register. Thus, this interrupt/clear process is

Thermostat interrupt mode operation with FT = 2 is illustrated in Figure 4.

Figure 4. O.S. OUTPUT OPERATION EXAMPLE

In this example the DS75

is configured to have a

fault tolerance of 2.

O.S. Output - Comparator Mode

Conversions

Inactive

Active

Temperature

Inactive

Active

O.S. Output - Interrupt Mode

Assumes a read

has occurred