TMP302 Datasheet, PDF (9/21 Pages) Texas Instruments – TMP302 Easy-to-Use, Low-Power, Low-Supply Temperature Switch in Micropackage

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TMP302
SBOS488C – JUNE 2009 – REVISED AUGUST 2015
7.3 Feature Description
7.3.1 HYSTSET
If the temperature trip threshold is crossed, the open-drain, active low output (OUT) goes low and does not return
to the original high state (that is, V_S) until the temperature returns to a value within a hysteresis window set by
the HYSTSET pin. The HYSTSET pin allows the user to choose between a 5°C and a 10°C hysteresis window.
Table 2 lists the hysteresis window that corresponds to the HYSTSET setting.
Table 2. HYSTSET Window
HYSTSET
GND
V_S
THRESHOLD HYSTERESIS
5°C
10°C
For the specific case of the TMP302A device, if the HYSTSET pin is set to 10°C (that is, connected to V_S) and
the device is configured with a 60°C trip point (TRIPSET1 = V_S, TRIPSET0 = GND), when this threshold is
exceeded the output does not return to the original high state until it reaches 50°C. This case is more clearly
shown in Figure 9.
OUT
V_S
50°C
60°C
T_(TRIP)
Figure 9. TMP302A: HYSTSET = V_S, TRIPSET1 = V_S, TRIPSET0 = GND
7.4 Device Functional Modes
The TMP302 family of devices has a single functional mode. Normal operation for the TMP302 family of devices
occurs when the power-supply voltage applied between the V_S pin and GND is within the specified operating
range of 1.4 to 3.6 V. The temperature threshold is selected by connecting the TRIPSET0 and TRIPSET1 pins to
either the GND or V_S pins (see Table 1). Hysteresis is selected by connecting the HYSTSET pin to either the
GND or V_S pins (see Table 2). The output pin, OUT, remains high when the temperature is below the selected
temperature threshold. The OUT pin remains low when the temperature is at or above the selected temperature
threshold. The OUT pin returns from a low state back to the high state based upon the amount of selected
hysteresis (see the HYSTSET section).
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