DS1825U+ Maxim Integrated Products, DS1825U+ Datasheet - Page 18

• Manufacturer Part Number: DS1825U+
• Description: IC THERMOMETER DIGITAL 8-USOP
• Manufacturer: Maxim Integrated Products

Specifications of DS1825U+

• Function: Thermometer, Thermostat
• Topology: Register Bank, Scratchpad
• Sensor Type: Internal
• Sensing Temperature: -55°C ~ 125°C
• Output Type: Digital
• Output Alarm: Yes
• Output Fan: No
• Voltage - Supply: 3 V ~ 3.7 V
• Operating Temperature: -55°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
• Temperature Threshold: Programmable
• Full Temp Accuracy: +/- 0.5 C
• Digital Output - Bus Interface: 1-Wire
• Digital Output - Number Of Bits: 9 bit to 12 bit
• Supply Voltage (max): 3.7 V
• Supply Voltage (min): 3 V
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 55 C
• Supply Current: 1.5 mA
• Ic Output Type: Digital
• Sensing Accuracy Range: ± 0.5°C
• Supply Voltage Range: 3V To 3.7V
• Resolution (bits): 12bit
• Sensor Case Style: µSOP
• No. Of Pins: 8
• Accuracy %: 0.5°C
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Figure 16. DETAILED MASTER READ 1 TIMING
Figure 17. RECOMMENDED MASTER READ 1 TIMING
DS1825 OPERATION EXAMPLE
In this example there are multiple DS1825s on the bus and they are using parasite power. The bus master initiates
a temperature conversion in a specific DS1825 and then reads its scratchpad and recalculates the CRC to verify
the data.
MASTER MODE
1-WIRE BUS
GND
1-WIRE BUS
GND
V
V
PU
PU
RX
RX
RX
RX
TX
TX
TX
TX
TX
TX
TX
TX
TX
TX
TX
small
T
INT
=
small
T
RC
DQ line held high by
DATA (LSB FIRST)
=
64-bit ROM code
64-bit ROM code
T
strong pullup
INT
9 data bytes
Presence
Presence
Presence
> 1 ms
Reset
Reset
Reset
BEh
F0h
55h
44h
55h
VIH of Master
LINE TYPE LEGEND
Bus master pulling low
Resistor pullup
Master issues reset pulse.
Master issues reset pulse.
Master issues reset pulse.
DS1825s respond with presence pulse.
Master issues Search ROM command and builds
Crossreference Table
DS1825s respond with presence pulse.
Master issues Match ROM command for desired address
Master sends DS1825 ROM code.
Master issues Convert T command.
Master applies strong pullup to DQ for the duration of the
conversion (t
DS1825s respond with presence pulse.
Master issues Match ROM command.
Master sends DS1825 ROM code.
Master issues Read Scratchpad command.
Master reads entire scratchpad including CRC. The master
then recalculates the CRC of the first eight data bytes from the
scratchpad and compares the calculated CRC with the read
CRC (byte 9). If they match, the master continues; if not, the
read operation is repeated.
18 of 21
15 ms
15 ms
T
RC
conv
).
VIH of Master
Master samples
COMMENTS
Master samples