DS9108
Concrete Temperature
Monitor
www.maxim-ic.com
GENERAL DESCRIPTION
FEATURES
This product is a sealed plastic stick containing three
DS1921G iButtons®. The iButtons are connected in
parallel through metal plates that are spot-welded to
the IO and GND contact, respectively. Two stranded
wires protruding from the top end of the stick allow
for a 1-Wire® reader/write to make contact to the
iButtons for setup and data retrieval. Electrically, the
product is specified by the DS1921G data sheet, with
the proper scaling (e.g., current ×3, capacitance ×3).
The mechanical and thermal characteristics of the
module are specified in this document.
Three DS1921G networked to monitor temperate
at the top, bottom and center of the stick
Connects to 1-Wire reader/writer through color-
coded 18 AWG (1 mm Ø) stranded wires with ½
inch (1.3 cm) stripped ends
Electrically compatible to the DS1921G
Thermochron iButton (3 in parallel)
Sealed against liquid intrusion
Module position information stored in DS1921G
memory
APPLICATIONS
ORDERING INFORMATION
PART
TEMP RANGE
-20°C to 65°C
-20°C to 65°C
-20°C to 65°C
-20°C to 65°C
PIN-PACKAGE
8” (20.3 cm) depth*
10” (25.4 cm) depth
12” (30.5 cm) depth
15” (38.1 cm) depth
•
Concrete Maturity Monitoring
DS9108-080
DS9108-100
DS9108-120
DS9108-150
Shipped in bulk with the wires bundled with a tie
* Indicates depth of concrete to monitor, actual stick
length is 0.25” (0.6 cm) less then depth
TYPICAL OPERATING CIRCUIT
BLOCK DIAGRAM
Metal plates welded
to iButtons
Stranded wire
Ends twisted
VCC
RPUP
*
U1
U2
U3
IO
Red
wire
DS1921G
#3
BOTTOM
DS1921G
#2
MIDDLE
DS1921G
#1
TOP
Temperature
Monitor
Portable
1-Wire
reader
GND
Black
wire
IO
GND
Red
Transition wire to
metal plate
Black
* See Application Note 3829 for Rpup resistor size selection.
iButton and 1-Wire are registered trademarks of Dallas
Semiconductor.
Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device
may be simultaneously available through various sales channels. For information about device errata, click here: www.maxim-ic.com/errata.
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REV: 091806