DS18B20-PAR

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resolution, bits 1 and 0 are undefined, and for 9-bit resolution bits 2, 1 and 0 are undefined. Table 2 gives

examples of digital output data and the corresponding temperature reading for 12-bit resolution

conversions.

TEMPERATURE REGISTER FORMAT Figure 3

bit 7

bit 6

bit 5

bit 4

bit 3

bit 2

bit 1

bit 0

LS Byte

2

3

2

2

2

1

2

0

2

-1

2

-2

2

-3

2

-4

bit 15

bit 14

bit 13

bit 12

bit 11

bit 10

bit 9

bit 8

MS Byte

S

S

S

S

S

2

6

2

5

2

4

TEMPERATURE/DATA RELATIONSHIP Table 2

TEMPERATURE

DIGITAL OUTPUT

(Binary)

DIGITAL OUTPUT

(Hex)

+85°C*

0000 0101 0101 0000

0550h

+25.0625°C

0000 0001 1001 0001

0191h

+10.125°C

0000 0000 1010 0010

00A2h

+0.5°C

0000 0000 0000 1000

0008h

0°C

0000 0000 0000 0000

0000h

-0.5°C

1111 1111 1111 1000

FFF8h

-10.125°C

1111 1111 0101 1110

FF5Eh

-25.0625°C

1111 1110 0110 1111

FE6Fh

-55°C

1111 1100 1001 0000

FC90h

*The power-on reset value of the temperature register is +85°C

OPERATION – ALARM SIGNALING

After the DS18B20-PAR performs a temperature conversion, the temperature value is compared to the

4). The sign bit (S) indicates if the value is positive or negative: for positive numbers S = 0 and for

explained in the MEMORY section of this datasheet.

bit 7

bit 6

bit 5

bit 4

bit 3

bit 2

bit 1

bit 0

S

2

6

2

5

2

4

2

3

2

2

2

1

2

0

updated after every temperature measurement; therefore, if the alarm condition goes away, the flag will

be turned off after the next temperature conversion.