CALIBRATING FOR IMPROVED ACCURACY

0.8

0.6

0.4

0.2

0

0.2

0.4

0.6

-

-

-

Temperature( C)

°

-40

-20

0

20

40

60

130

Slope1

MAX

Slope1

MIN

Slope2

MAX

Slope2

MIN

Slope3

MIN

100 110 120

80 90

70

50

30

10

-30

-10

Slope3

MAX

Accuracy

=Acc

+ T

Slope

D ´

(worst-case)

25°C)

uracy

(

(1)

TMP112

There are many temperature monitoring applications that require better than 0.5°C accuracy over a limited

temperature range. Knowing the offset of a temperature sensor at a given temperature in conjunction with the

average temperature span (slope) error over a fixed range makes it possible to achieve this improved accuracy.

The TMP112 has three distinct slope regions that conservatively approximate its inherent curvature:

1. Slope1 applies over –40°C to +25°C

2. Slope2 applies over +25°C to +85°C

3. Slope3 applies over +85°C to +125°C

These slopes are defined in Table 14 and shown in Figure 19.It is important to note that each slope is increasing

with respect to 25°C.

Table 14. Specifications for User-Calibrated Systems

PARAMETER

CONDITION

MIN

MAX

UNIT

–7

0

m°C/°C

Average Slope

(Temperature Error vs

0

+5

m°C/°C

0

+8

m°C/°C

(1)

User-calibrated temperature accuracy can be within ±1LSB because of quantization noise.

Figure 19. Accuracy and Slope Curves versus Temperature

Equation 1 determines the worst-case accuracy at a specific temperature:

16

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