ADT6401 Datasheet, PDF (1/12 Pages) Analog Devices – Low Cost, 2.7 V to 5.5 V, Pin-Selectable Temperature Switches in SOT-23

Low Cost, 2.7 V to 5.5 V, Pin-Selectable
Temperature Switches in SOT-23
ADT6401/ADT6402
FEATURES
±0.5°C (typical) threshold accuracy
Pin-selectable trip points from
−45°C to +5°C in 10°C increments (undertemperature)
45°C to 115°C in 10°C increments (overtemperature)
Maximum operating temperature of 125°C
Open-drain output (ADT6401)
Push-pull output (ADT6402)
Pin-selectable hysteresis of 2°C and 10°C
Supply current of 30 μA (typical)
Space-saving, 6-lead SOT-23 package
APPLICATIONS
Medical equipment
Automotive
Cell phones
Hard disk drives
Personal computers
Electronic test equipment
Domestic appliances
Process control
GENERAL DESCRIPTION
The ADT6401/ADT6402 are trip point temperature switches
available in a 6-lead SOT-23 package. Each part contains an
internal band gap temperature sensor for local temperature
sensing. When the temperature crosses the trip point setting,
the logic output is activated. The ADT6401 logic output is
active low and open-drain. The ADT6402 logic output is active
high and push-pull. The temperature is digitized to a resolution
of 0.125°C (11-bit). The pin-selectable trip point settings are
10°C apart starting from −45°C to +5°C for undertemperature
switching, and from 45°C to 115°C for overtemperature
switching.
These devices typically consume 30 μA of supply current. Hystere-
sis is pin selectable at 2°C and 10°C. The temperature switch is
specified to operate over the supply range of 2.7 V to 5.5 V.
When the ADT6401/ADT6402 are used for monitoring tempera-
tures from 45°C to 115°C, the logic output pin becomes active
when the temperature goes higher than the selected trip point
temperature.
FUNCTIONAL BLOCK DIAGRAM
V_CC
GND
4
5
Σ-Δ
TEMPERATURE-TO-
DIGITAL CONVERTER
ADT6401
COMPARATOR
6 TOVER/TUNDER
S2 1
S1 2
S0 3
TRIP POINT AND
HYSTERESIS
DECODING
2ºC/10ºC
Figure 1.
When the ADT6401/ADT6402 are used for monitoring tempera-
tures from −45°C to +5°C, the logic output pin becomes active
when the temperature goes lower than the selected trip point
temperature.
PRODUCT HIGHLIGHTS
1. Σ-Δ based temperature measurement gives high accuracy
and noise immunity.
2. Wide operating temperature range from −55°C to +125°C.
3. ±0.5°C typical accuracy from −45°C to +115°C.
4. Pin-selectable threshold settings from −45°C to +115°C in
10°C increments.
5. Supply voltage is 2.7 V to 5.5 V.
6. Supply current of 30 μA.
7. Space-saving, 6-lead SOT-23 package.
8. Pin-selectable temperature hysteresis of 2°C or 10°C.
9. Temperature resolution of 0.125°C.
Rev. 0
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