DS18S20-PAR+T&R Maxim Integrated Products, DS18S20-PAR+T&R Datasheet - Page 17

• Manufacturer Part Number: DS18S20-PAR+T&R
• Description: Board Mount Temperature Sensors Prgmble Resolution 1-Wire Parasite Pwr
• Manufacturer: Maxim Integrated Products

Specifications of DS18S20-PAR+T&R

• Full Temp Accuracy: +/- 0.5 C
• Package / Case: TO-92
• Digital Output - Bus Interface: Serial (1-Wire)
• Digital Output - Number Of Bits: 9 bit
• Maximum Operating Temperature: + 100 C
• Minimum Operating Temperature: - 55 C
• Output Type: Digital
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

DS18S20-PAR OPERATION EXAMPLE 2
In this example there are multiple DS18S20-PARs on the bus. The bus master initiates a temperature
conversion in a specific DS18S20-PAR and then reads its scratchpad and recalculates the CRC to verify
the data.
DS18S20-PAR OPERATION EXAMPLE 3
In this example there is only one DS18S20-PAR on the bus. The bus master initiates a temperature
conversion then reads the DS18S20-PAR scratchpad and calculates a higher resolution result using the
data from the temperature, COUNT REMAIN and COUNT PER °C registers.
MASTER MODE
MASTER MODE
TX
RX
TX
TX
TX
TX
TX
RX
TX
TX
TX
RX
TX
TX
TX
TX
TX
RX
TX
TX
RX
TX
RX
TR
-
DATA (LSB FIRST)
DATA (LSB FIRST)
DQ line held high by
DQ line held high by
64-bit ROM code
64-bit ROM code
strong pullup
strong pullup
9 data bytes
9 data bytes
Presence
Presence
Presence
Presence
Presence
Reset
Reset
Reset
Reset
Reset
BEh
CCh
CCh
BEh
55h
44h
55h
44h
-
DS18S20-PARs respond with presence pulse.
Master sends DS18S20-PAR ROM code.
DS18S20-PARs respond with presence pulse.
Master sends DS18S20-PAR ROM code.
DS18S20-PAR responds with presence pulse.
DS18S20-PAR responds with presence pulse.
DS18S20-PAR responds with presence pulse.
Master issues reset pulse.
Master issues Match ROM command.
Master issues Convert T command.
Master applies strong pullup to DQ for the duration of the
conversion (t
Master issues reset pulse.
Master issues Match ROM command.
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.
Master issues reset pulse.
Master issues Skip ROM command.
Master issues Convert T command.
Master applies strong pullup to DQ for the duration of the
conversion (t
Master issues reset pulse.
Master issues Skip ROM command.
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. The master also calculates the
TEMP_READ value and stores the contents of the COUNT
REMAIN and COUNT PER °C registers.
Master issues reset pulse.
CPU calculates extended resolution temperature using the
equation in the OPERATION - MEASURING
TEMPERATURE section of this datasheet.
17 of 20
conv
conv
).
).
COMMENTS
COMMENTS