DS1620 参数 Datasheet PDF下载

DS1703K

DS1620/DS1720 OPERATION

DS1620/DS1720 Thermometer Tab

If the DS1620 or DS1720 is selected in the

Device Selection

form, the

Thermometer

tab shown in

Figure 5 is loaded. With this screen displayed, the software continually reads the temperature and

configuration registers from the part. The readings happen approximately 2.5s after the previous

reading ends. The contents of the temperature register are shown on the form next to the

thermometer in hexadecimal, Celsius, and Fahrenheit. The thermometer graphic also updates and

tracks the Celsius temperature. The High Temperature Threshold (TH) and Low Temperature

Threshold (TL) flags from the configuration register can be monitored in the bottom right of the

form.

Figure 5. DS1620/DS1720 Thermometer Tab

The upper left corner of the

Temperature Measurement

section has two buttons relating to

temperature conversions. Pressing the

Start Temperature Conversion

button on this section sends the

Start Convert T (EEh) command to the part. Pressing the

Stop Temperature Conversion

button sends

the Stop Convert T (22h) command to the part.

In the

Device Preferences

section of the form there are two option buttons used to determine the

conversion mode. These buttons allow the user to select either the 1-shot or continuous conversion

mode. Selecting either option causes the software to issue a Read Config (ACh) command, modify

the 1SHOT bit (bit 0), and then issue a Write Config (0Ch) command.

The final section of this form selects either 9-bit or higher resolution temperature calculations. If the

9-bit option is selected, only the contents of the temperature register are shown. However, selecting

the higher resolution option causes the software to issue Read Counter (A0h) and Read Slope (A9h)

commands during each temperature reading. The temperature is then calculated using Equation 1,

where TEMP_READ is the value obtained by reading the temperature and then truncating the LSb.

TEMPERATURE

=

TEMP_READ

-

0

.

25

+

(

COUNT_PER_C

-

COUNT_REMAIN

)

COUNT_PER_C

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