DS18B20+PAR Maxim Integrated Products, DS18B20+PAR Datasheet - Page 4

• Manufacturer Part Number: DS18B20+PAR
• Description: IC THERM MICROLAN PROG-RES TO-92
• Manufacturer: Maxim Integrated Products

Specifications of DS18B20+PAR

• Function: Thermometer, Thermostat
• Topology: Register Bank, Scratchpad
• Sensor Type: Internal
• Sensing Temperature: -55°C ~ 100°C
• Output Type: 1-Wire®
• Output Alarm: Yes
• Output Fan: No
• Voltage - Supply: 3 V ~ 5.5 V
• Operating Temperature: -55°C ~ 100°C
• Mounting Type: Through Hole
• Package / Case: TO-92-3 (Standard Body), TO-226
• Temperature Threshold: Programmable
• Full Temp Accuracy: +/- 0.5 C
• Digital Output - Bus Interface: 1-Wire
• Digital Output - Number Of Bits: 12 bit
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 3 V
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 55 C
• Supply Current: 1.5 mA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

resolution, bits 1 and 0 are undefined, and for 9-bit resolution bits 2, 1 and 0 are undefined. Table 2 gives
examples of digital output data and the corresponding temperature reading for 12-bit resolution
conversions.
TEMPERATURE REGISTER FORMAT Figure 3
TEMPERATURE/DATA RELATIONSHIP Table 2
OPERATION – ALARM SIGNALING
After the DS18B20-PAR performs a temperature conversion, the temperature value is compared to the
user-defined two’s complement alarm trigger values stored in the 1-byte T
4). The sign bit (S) indicates if the value is positive or negative: for positive numbers S = 0 and for
negative numbers S = 1. The T
when the device is powered down. T
explained in the MEMORY section of this datasheet.
T
Only bits 11 through 4 of the temperature register are used in the T
are 8-bit registers. If the result of a temperature measurement is higher than or equal to T
or equal to T
updated after every temperature measurement; therefore, if the alarm condition goes away, the flag will
be turned off after the next temperature conversion.
MS Byte
H
LS Byte
AND T
bit 7
S
L
L
, an alarm condition exists and an alarm flag is set inside the DS18B20-PAR. This flag is
REGISTER FORMAT Figure 4
bit 15
bit 7
*The power-on reset value of the temperature register is +85°C
2
S
TEMPERATURE
3
bit 6
+25.0625°C
-25.0625°C
+10.125°C
2
-10.125°C
6
+85°C*
+0.5°C
-0.5°C
-55°C
0°C
bit 14
bit 6
2
S
2
bit 5
H
2
5
and T
H
and T
bit 13
bit 5
2
DIGITAL OUTPUT
0000 0101 0101 0000
0000 0001 1001 0001
0000 0000 1010 0010
0000 0000 0000 1000
0000 0000 0000 0000
1111 1111 1111 1000
1111 1111 0101 1110
1111 1110 0110 1111
1111 1100 1001 0000
S
L
1
registers are nonvolatile (EEPROM) so they will retain data
bit 4
L
2
can be accessed through bytes 2 and 3 of the scratchpad as
4
(Binary)
4 of 19
bit 12
bit 4
2
S
0
bit 3
2
3
bit 11
bit 3
2
S
-1
DIGITAL OUTPUT
H
bit 2
and T
2
2
00A2h
FF5Eh
FE6Fh
FC90h
FFF8h
0550h
0191h
0008h
0000h
(Hex)
bit 10
H
L
bit 2
2
2
comparison since T
and T
-2
6
bit 1
2
1
L
registers (see Figure
bit 1
bit 9
2
2
-3
5
H
or lower than
DS18B20-PAR
bit 0
2
0
H
and T
bit 0
bit 8
2
2
-4
4
L