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TEMPERATURE/DATA RELATIONSHIP Table 2

TEMPERATURE

DIGITAL OUTPUT

(Binary)

DIGITAL OUTPUT

(Hex)

+125°C*

0111 1101

7Dh

+85°C

0101 0101

55h

+25°C

0001 1001

19h

0°C

0000 0000

00h

-1°C

1111 1111

FFh

-25°C

1110 0111

E7h

-55°C

1100 1001

C9h

HIGH-RESOLUTION TEMPERATURE READINGS

The user can calculate temperature values with higher than 8-bit resolution using the data remaining in

the counter and slope accumulator when the temperature conversion is complete. To do this the user must

first read the temperature from the 8-bit temperature register. This value is called TEMP_READ in the

high-resolution equation (see Eq. 1). The 9-bit counter value must then be obtained by issuing the Read

Counter [A0h] command. This value is the count remaining in the counter at the end of the gate period

and is called COUNT_REMAIN in Eq. 1. Next the Load Counter [41h] command must be issued, which

loads the 9-bit slope accumulator value into the counter register. The slope accumulator value (called

COUNT_PER_C in Eq. 1) can then be read from the counter by again issuing the Read Counter [A0h]

command. The slope accumulator value is called “COUNT_PER_C” because it represents the number of

counts needed for an accurate measurement at a given temperature (i.e., the counts per degree C). The

high-resolution temperature can then be calculated using Eq. 1:

Eq. 1)

TEMPERATURE = TEMP_READ

C

PER

COUNT

REMAIN

COUNT

C

PER

COUNT

_

_

)

_

_

_

(

−

High-resolution temperature readings cannot be used while in continuous conversion mode. Also, the

Read Counter [A0h] and Load Counter [41h] commands must not be used while in continuous conversion

mode.