© Semiconductor Components Industries, LLC, 2002

June, 2002 – Rev. 1

1

Publication Order Number:

NCT22/D

NCT22, NCT24

Low Cost Single Trip Point

Temperature Sensor

The NCT22 and NCT24 are programmable solid state temperature

sensors designed to replace mechanical switches in sensing and

control applications. Both devices integrate the temperature sensor

with a voltage reference and all required detector circuitry. The desired

temperature set point is set by the user with a single external resistor.

Ambient temperature is sensed and compared to the programmed

setpoint. The OUT and OUT outputs are driven to their active state

when the measured temperature exceeds the programmed setpoint.

The NCT22 has a power supply voltage range of 4.5 V to 18 V

while the NCT24 operates over a power supply range of 2.7 V to 4.5 V.

Both devices are useable over a temperature range of –40

°C to

+125

°C. Both devices feature low supply current making them

suitable for many portable applications.

The devices are offered in surface mount packages.

Features

Resistor

Applications

Figure 1. Heat Monitor for Smoke Detector

NCT22

CONTROL

ASIC

NC

NC

GND

NC

OUT

OUT

ALARM

+

–

1

5

6

4

7

8

3

Sounder

+9 V

9 V

Battery

Sensor

2

SOIC–8

D SUFFIX

CASE 751

PIN CONNECTIONS

See detailed ordering and shipping information in the package

dimensions section on page 5 of this data sheet.

ORDERING INFORMATION

1

8

8

7

6

5

1

2

3

4

N/C

N/C

(Top View)

OUT

OUT

GND

N/C

NCT22

NCT24

NCTxx

ALYW

xx = 22 or 24

A

= Assembly Location

L

= Wafer Lot

Y

= Year

W

= Work Week

MARKING

DIAGRAM

1

8

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