DS1921H/Z
9) Voltage above which, during a rising edge on IO, a logic 1 is detected.
10) The I-V characteristic is linear for voltages less than 1V.
11)
ε represents the time required for the pull-up circuitry to pull the voltage on IO up from VIL to
VTH.
12)
δ represents the time required for the pull-up circuitry to pull the voltage on IO up from VIL to the
input high threshold of the bus master.
13) This number was derived from a test conducted by Cemagref in Antony, France, in July of 2000.
http://www.cemagref.fr/English/index.htm Test Report No. E42
14) The number of temperature conversions (= Samples) possible with the built-in energy source
depends on the operating and storage temperature of the device. When not in use for a mission,
the RTC oscillator should be turned off and device should be stored at a temperature not
exceeding +25°C. Under this condition the shelf life time is 10 years minimum.
15) Highlighted numbers are not in compliance with the published iButton standards. See comparison
table below.
16) These values are derived from simulation across process, voltage, and temperature and are not
production tested.
17)
Total accuracy is ∆ϑ plus 1/16°C quantization due to the 1/8°C digital resolution of the device.
18) WARNING: Not for use as the sole or primary 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 other primary and redundant 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 is recommended only as a supplemental and redundant
information source. User shall be responsible for proper use, storage, and calibration of this
product.
Standard Values
Standard Speed Overdrive Speed
min max min max
61µs
(undef.) 65µs 1)
DS1921H/Z Values
Standard Speed Overdrive Speed
min max
(undef.) 8µs 1)
Parameter
Name
tSLOT (incl. tREC
tRSTL
tPDH
tPDL
min
max
(undef.)
80µs
)
(undef.) 7µs
(undef.) 48µs
480µs
15µs
60µs
60µs
80µs
6µs
24µs
16µs
540µs
15µs
60µs
60µs
640µs
60µs
48µs
1.1µs
7.5µs
6µs
60µs
240µs
120µs
2µs
8µs
6µs
6µs
270µs
120µs
24µs
15µs
tW0L
1) Intentional change, longer recovery time between time slots.
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DALLAS [ DALLAS SEMICONDUCTOR ]
