Datasheet

STTS751 Addr/Therm output
Doc ID 16483 Rev 5 23/36
6 Addr/Therm output
The Addr/Therm pin functions normally as an output to alert the system of an over
temperature condition. It is open drain and requires a pull-up resistor. During power-up, the
pull-up value is sensed by the STTS751 to determine what its slave address will be as
depicted in Tabl e 1.
The Therm
output is asserted low whenever the temperature exceeds the Therm limit
(address 20h). Only the upper 8 bits of the temperature register are used in the
comparison with the Therm limit. Once asserted, Therm
will remain asserted until
temperature falls below the Therm limit minus the therm hysteresis value. For example, if
the Therm limit is 25 °C, and the therm hysteresis value is 10 °C, the Therm
output will
assert when the temperature exceeds 25 °C. It will remain asserted until the temperature
falls down to or below 15 °C (25 – 10).
This pin can be used to control a fan or other failsafe device as shown in Figure 4 on page 8.
Figure 7 below shows how the Therm
output functions.
Figure 7. Therm
output
AM03033v1
Time
Addr/Therm
Therm limit
Therm Limit minus
Therm Hysteresis
Temperature
Therm
Hysteresis