DS1722

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Temperature/Data Relationships

Table 3

Address

Location

S

02h

MSb

(unit =

°C)

LSb

0

0

0

0

01h

TEMPERATURE

DIGITAL OUTPUT

(BINARY)

DIGITAL OUTPUT

(HEX)

+120

°C

0111 1000 0000 0000

7800h

+25.0625

°C

0001 1001 0001 0000

1910h

+10.125

°C

0000 1010 0010 0000

0A20h

+0.5

°C

0000 0000 1000 0000

0080h

0

°C

0000 0000 0000 0000

0000h

-0.5

°C

1111 1111 1000 0000

FF80h

-10.125

°C

1111 0101 1110 0000

F5E0h

-25.0625

°C

1110 0110 1111 0000

E6F0h

-55

°C

1100 1001 0000 0000

C900h

OPERATION-Programming

The area of interest in programming the DS1722 is the Configuration register. All programming is done

via the SPI or 3-wire communication interface by selecting the appropriate address of the desired register

location. Table 4 illustrates the addresses for the two registers (configuration and temperature) of the

DS1722.

Register Address Structure

Table 4

Read Address

Write Address

Active Register

00h

80h

Configuration

01h

No access

Temperature LSB

02h

No access

Temperature MSB

CONFIGURATION REGISTER PROGRAMMING

The configuration register is accessed in the DS1722 with the 00h address for reads and the 80h address

for writes. Data is read from or written to the configuration register MSb first for SPI communication and

LSb first for 3-wire communication. The format of the register is illustrated in Figure 2. The effect each

bit has on DS1722 functionality is described below along with the power-up state of the bit. The entire

register is volatile, and thus it will power-up in the default state.