LM19

January 26, 2010

2.4V, 10

μA, TO-92 Temperature Sensor

General Description

The LM19 is a precision analog output CMOS integrated-cir-

cuit temperature sensor that operates over a −55°C to +130°

C temperature range. The power supply operating range is

+2.4 V to +5.5 V. The transfer function of LM19 is predomi-

nately linear, yet has a slight predictable parabolic curvature.

The accuracy of the LM19 when specified to a parabolic

transfer function is ±2.5°C at an ambient temperature of +30°

C. The temperature error increases linearly and reaches a

maximum of ±3.8°C at the temperature range extremes. The

temperature range is affected by the power supply voltage. At

a power supply voltage of 2.7 V to 5.5 V the temperature

range extremes are +130°C and −55°C. Decreasing the pow-

er supply voltage to 2.4 V changes the negative extreme to

−30°C, while the positive remains at +130°C.

The LM19's quiescent current is less than 10

μA. Therefore,

self-heating is less than 0.02°C in still air. Shutdown capability

for the LM19 is intrinsic because its inherent low power con-

sumption allows it to be powered directly from the output of

many logic gates or does not necessitate shutdown at all.

Applications

Features

Key Specifications

±2.5 °C (max)

±3.5 to ±3.8 °C (max)

+2.4V to +5.5V

10 μA (max)

±0.4 % (typ)

160 Ω (max)

 

−2.5 mV (max)

Typical Application

20004002

V

or

where:

T is temperature, and V

Output Voltage vs Temperature

20004024

FIGURE 1. Full-Range Celsius (Centigrade) Temperature Sensor (−55°C to +130°C)

Operating from a Single Li-Ion Battery Cell

© 2010 National Semiconductor Corporation

200040

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