Temperature errors associated with non-ideality may be re-

duced in a specific temperature range of concern through

use of the offset registers (11h and 12h).

Figure 14 shows

how the offset register may be used to compensate for the

non-ideality errors shown in

Figure 13. For the case of

non-ideality=1.008, the offset register was set to −0.5˚C

resulting in the calculated residual error as shown in

Figure

14. This offset has resulted in an error of less than 0.05˚C for

the temperatures measured in the critical range between 60

to 100˚C. This method yeilds a first order correction factor.

requesting further information on our recommended setting

of the offset register for different processor types.

20033737

Error Caused by Non-Ideality Factor

FIGURE 12.

20033736

Errors Induced when Temperature Sensor is Not

Calibrated to Typical Non-Ideality

FIGURE 13.

20033738

Compensating for an Untargeted Non-Ideality Factor

FIGURE 14.

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