DS1920 Maxim, DS1920 Datasheet - Page 16

• Manufacturer Part Number: DS1920
• Description: The DS1920 provides direct-to-digital 9-bit temperature readings over a range of -55°C to +100°C in 0
• Manufacturer: Maxim

DS1920 MEMORY AND CONTROL FUNCTION COMMANDS Table 2
NOTES:
1. Temperature conversion takes up to 0.75 seconds. After receiving the Convert Temperature
2. After receiving the Copy Scratchpad command, the data line for the DS1920 must be held high for at
READ/WRITE TIMING DIAGRAM Figure 11
Write-1 Time Slot
Convert
Temperature
Read Scratchpad
Write Scratchpad
Copy Scratchpad
Recall
INSTRUCTION
command, the data line for the DS1920 must be held high for at least 0.75 seconds to provide power
during the conversion process. As such, no other activity may take place on the 1-Wire bus for at least
this period after a Convert Temperature command has been issued.
least 10ms to provide power during the copy process. As such, no other activity may take place on the
1-Wire bus for at least this period after a Copy Scratchpad command has been issued.
Initiates temperature
conversion
Reads bytes from scratchpad
and reads CRC byte.
Writes bytes into scratchpad
at addresses 2 and 3 (TH and
TL temperature triggers).
Copies Scratchpad into
nonvolatile memory
(addresses 2 and 3 only).
Recalls values stored in
nonvolatile memory into
scratchpad (temperature
triggers).
TEMPERATURE CONVERSION COMMANDS
DESCRIPTION
RESISTOR
MASTER
MEMORY COMMANDS
16 of 22
60µs ≤ t
1µs ≤ t
1µs ≤ t
PROTOCOL
REC
LOW1
SLOT
BEh
4Eh
B8h
44h
48h
< ∞
< 120µs
< 15µs
bytes at addr. 2 and
AFTER ISSUING
<read up to 9 data
<write data into 2
PROTOCOL
strong pullup
strong pullup
1-Wire BUS
addr. 3>
bytes>
idle
NOTES
DS1920
1
2