DS1620S Maxim Integrated Products, DS1620S Datasheet - Page 3

• Manufacturer Part Number: DS1620S
• Description: IC THERMOMETER/STAT DIG 8-SOIC
• Manufacturer: Maxim Integrated Products

Specifications of DS1620S

• Function: Thermometer, Thermostat
• Topology: Comparator, Register Bank
• Sensor Type: Internal
• Sensing Temperature: -55°C ~ 125°C
• Output Type: Digital
• Output Alarm: Yes
• Output Fan: No
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -55°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (5.3mm Width), 8-SOP, 8-SOEIAJ
• Full Temp Accuracy: +/- 2 C
• Digital Output - Bus Interface: Serial (3-Wire)
• Digital Output - Number Of Bits: 9 bit
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 55 C
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

DS1620
DS1620 FUNCTIONAL BLOCK DIAGRAM Figure 1
The DS1620 measures temperature using a bandgap-based temperature sensor. The temperature reading
is provided in a 9–bit, two’s complement reading by issuing a READ TEMPERATURE command. The
data is transmitted serially through the 3–wire serial interface, LSB first. The DS1620 can measure
temperature over the range of -55°C to +125°C in 0.5°C increments. For Fahrenheit usage, a lookup table
or conversion factor must be used.
Since data is transmitted over the 3–wire bus LSB first, temperature data can be written to/read from the
th
DS1620 as either a 9–bit word (taking
low after the 9
(MSB) bit), or as two transfers of 8–bit
RST
words, with the most significant 7 bits being ignored or set to 0, as illustrated in Table 3. After the MSB,
the DS1620 will output 0s.
Note that temperature is represented in the DS1620 in terms of a ½°C LSB, yielding the 9–bit format
shown in Figure 2.
TEMPERATURE, TH, and TL REGISTER FORMAT Figure 2
MSB
LSB
X
X
X
X
X
X
X
1
1
1
0
0
1
1
1
0
T = -25°C
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