DS1922T-F5 MAXIM [Maxim Integrated Products], DS1922T-F5 Datasheet - Page 3

• Manufacturer Part Number: DS1922T-F5
• Description: Temperature Logger iButton With 8kB Datalog Memory
• Manufacturer: MAXIM [Maxim Integrated Products]

Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Note 7:
Note 8:
Note 9:
Note 10:
Note 11:
Note 12:
Note 13:
Note 14:
Note 15:
Note 16:
Note 17:
Note 18:
Note 19:
Note 20:
1)
I/O Pin, 1-Wire Read
Read Low Time
(Notes 1, 14)
Read Sample Time
(Notes 1, 14)
Real Time Clock
Accuracy
Frequency Deviation
Temperature Converter
Conversion Time
(Note 15)
Thermal Response Time
Constant (Note 16)
Conv. Error Without
Software Correction
(Notes 17, 19)
Conv. Error With Software
Correction (Notes 18, 19)
t
t
t
t
t
Intentional change, longer recovery time requirement due to modified 1-Wire front end.
SLOT
RSTL
PDH
PDL
W0L
PARAMETER
(incl. t
NAME
System Requirement
Maximum allowable pullup resistance is a function of the number of 1-Wire devices in the system and 1-Wire recovery times. The
specified value here applies to systems with only one device and with the minimum 1-Wire recovery times. For more heavily
loaded systems, an active pullup such as that found in the DS2480B may be required.
Capacitance on the data pin could be 800pF when V
after V
V
Voltage below which, during a falling edge on I/O, a logic '0' is detected.
The voltage on I/O needs to be less or equal to V
Voltage above which, during a rising edge on I/O, a logic '1' is detected.
After V
The I-V characteristic is linear for voltages less than 1V.
The earliest recognition of a negative edge is possible at t
Highlighted numbers are NOT in compliance with the published iButton standards. See comparison table below.
Interval during the negative edge on I/O at the beginning of a Presence Detect pulse between the time at which the voltage is
90% of V
ε represents the time required for the pullup circuitry to pull the voltage on I/O up from V
δ represents the time required for the pullup circuitry to pull the voltage on I/O up from V
master.
To conserve battery power, use 8-bit temperature logging whenever possible.
This number was derived from a test conducted by Cemagref in Antony, France, in July of 2000.
http://www.cemagref.fr/English/index.htm
Includes +0.1/-0.2
Assumes using calibration memory with calibration equations for error compensation. Includes +0.1/-0.2
measurement uncertainty. Guaranteed by design.
WARNING: Not for use as the sole method of measuring or tracking temperature and/or humidity in products and articles that
could affect the health or safety of persons, plants, animals, or other living organisms, including but not limited to foods,
beverages, pharmaceuticals, medications, blood and blood products, organs, flammable, and combustible products. User shall
assure that redundant (or other primary) methods of testing and determining the handling methods, quality, and fitness of the
articles and products should be implemented. Temperature and/or humidity tracking with this product, where the health or safety
of the aforementioned persons or things could be adversely affected, is only recommended when supplemental or redundant
information sources are used. Data logger products are 100% tested and calibrated at time of manufacture by Dallas
Semiconductor/Maxim to ensure that they meet all data sheet parameters, including temperature accuracy. User shall be
responsible for proper use and storage of this product. As with any sensor-based product, user shall also be responsible for
occasionally rechecking the temperature accuracy of the product to ensure it is still operating properly.
Guaranteed by design, not production tested to -40°C or 125°C.
REC
TL
, V
)
TH
PUP
TH
are a function of the internal supply voltage.
PUP
is crossed during a rising edge on I/O, the voltage on I/O has to drop by V
has been applied the parasite capacitance will not affect normal communications.
and the time at which the voltage is 10% of V
STANDARD SPEED
480µs
61µs
15µs
60µs
60µs
MIN
o
C calibration chamber measurement uncertainty.
t
τ
t
CONV
RESP
t
MSR
Δϑ
Δϑ
Δ
RL
F
STANDARD VALUES
(undef.)
(undef.)
240µs
120µs
MAX
60µs
Standard speed
Overdrive speed
Standard speed
Overdrive speed
-40°C to +85°C
0°C to +125°C
8-bit mode
16-bit mode (11 bits)
iButton package
Test Report No. E42.
OVERDRIVE SPEED
48µs
MIN
7µs
2µs
8µs
6µs
ILMAX
PUP
whenever the master drives the line low.
3 of 50
is first applied. If a 2.2kΩ resistor is used to pull up the data line, 2.5µs
REH
PUP
(undef.)
.
after V
MAX
80µs
24µs
16µs
6µs
TH
has been previously reached.
STANDARD SPEED
65µs
690µs
15µs
60µs
60µs
MIN
1)
HY
to be detected as logic '0'.
See Temperature Accuracy
See Temperature Accuracy
See RTC Accuracy Graphs
t
t
IL
IL
RL
RL
-300
-600
240
DS1922L/T VALUES
(undef.)
30
to V
to the input high threshold of the bus
63.5µs
5
1
720µs
287µs
120µs
+ δ
+ δ
MAX
TH
.
Graphs
Graphs
130
OVERDRIVE SPEED
o
C calibration chamber
9.5µs
7.5µs
70µs
MIN
2µs
7µs
DS1922L/DS1922T
1.95 - δ
15 - δ
1.95
+60
+60
600
15
75
(undef.)
MAX
80µs
28µs
12µs
7µs
month
PPM
min/
ms
°C
°C
µs
µs
s