TMP104

www.ti.com

SBOS564A

– NOVEMBER 2011 – REVISED NOVEMBER 2011

Negative numbers are represented in binary twos complement format. Following power-up or reset, the

Temperature Register reads 0

°C until the first conversion is complete.

DIGITAL OUTPUT

TEMPERATURE (

°C)

BINARY

HEX

128

0111 1111

7F

127

0111 1111

7F

100

0110 0100

64

80

0101 0000

50

75

0100 1011

4B

50

0011 0010

32

25

0001 1001

19

0

0000 0000

00

–1

1111 1111

FF

–25

1110 0111

E7

–55

1100 1001

C9

(1)

The resolution for the analog-to-digital converter (ADC) is 1

°C/count, where count is equal to the digital

output of the ADC.

For positive temperatures (for example, +50

°C):

Twos complement is not performed on positive numbers. Therefore, simply convert the number to binary

code, left-justified format. Denote a positive number with most significant bit (MSB) = 0.

Example: (+50

°C)/(1°C/count) = 50 = 32h = 0011 0010

For negative temperatures (for example,

–25°C):

Generate the twos complement of a negative number by complementing the absolute value binary number

and adding 1. Denote a negative number with MSB = 1.

Example: (|

–25°C|)/(1°C/count) = 25 = 19h = 0001 1001

Twos complement format: 1110 0110 + 1 = 1110 0111

Copyright

© 2011, Texas Instruments Incorporated

Submit Documentation Feedback

11

Product Folder Link(s): TMP104