ds1722st-r Maxim Integrated Products, Inc., ds1722st-r Datasheet - Page 5

• Manufacturer Part Number: ds1722st-r
• Description: Ds1722 Digital Thermometer With Spi/3-wire Interface
• Manufacturer: Maxim Integrated Products, Inc.

Temperature/Data Relationships Table 3
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
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.
MSb
2
S
-1
TEMPERATURE
Read Address
+25.0625°C
-25.0625°C
+10.125°C
-10.125°C
+120°C
+0.5°C
-0.5°C
-55°C
00h
01h
02h
0°C
2
2
-2
6
2
2
-3
5
2
2
-4
4
DIGITAL OUTPUT
0111 1000 0000 0000
0001 1001 0001 0000
0000 1010 0010 0000
0000 0000 1000 0000
0000 0000 0000 0000
1111 1111 1000 0000
1111 0101 1110 0000
1110 0110 1111 0000
1100 1001 0000 0000
Write Address
(unit = °C)
(BINARY)
No access
No access
80h
5 of 14
2
0
3
2
0
2
2
0
1
DIGITAL OUTPUT
Temperature MSB
Temperature LSB
Active Register
Configuration
(HEX)
0A20h
F5E0h
E6F0h
C900h
FF80h
7800h
1910h
0080h
0000h
LSb
2
0
0
Address
Location
02h
01h