DS9108
Concrete Temperature
Monitor
www.maxim-ic.com
GENERAL DESCRIPTION
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.
FEATURES
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
Concrete Maturity Monitoring
ORDERING INFORMATION
PART
DS9108-8#
DS9108-10#
DS9108-12#
DS9108-15#
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
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
V
CC
R
PUP
*
BLOCK DIAGRAM
Stranded wire
Ends twisted
U1
IO
Red
wire
Metal plates welded
to iButtons
U2
U3
Portable
1-Wire
reader
Temperature
Monitor
IO
GND
Black
Red
DS1921G
#1
TOP
DS1921G
#2
MIDDLE
DS1921G
#3
BOTTOM
GND
Black
wire
Transition wire to
metal plate
* 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.
1 of 3
REV: 102106
DS9108 Concrete Temperature Module
ABSOLUTE MAXIMUM RATINGS
Voltage Range on Any Pin Relative to Ground
Operating Temperature Range
Storage Temperature Range
See DS1921G Datasheet
-4°F to 149°F (-20°C to +65°C)
See DS1921G Datasheet
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only,
and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is
not implied. Exposure to the absolute maximum rating conditions for extended periods may affect device.
SPECIFICATIONS
(See DS1921G datasheet, T
A
= -4°F to 149°F (-20°C to +65°C) (Note 1))
PARAMETER
Weight
Physical Dimensions
Wire Length
Tensile Strength of Wires
Thermal Response Time
(Note 2)
CONDITIONS
MIN
TYP
2.5
72
See technical drawing
12.9
32.8
10
44.5
500
13.1
33.3
inches
cm
lbf
Newton
s
MAX
UNITS
ounces
grams
Note 1:
Assembled module production tested at 77°F (25
°
C).
Note 2:
Response time in water is the time required for the recorded value to read 63% of the temperature’s real variation.
Material: PVC with PVC cement and E-60NC black Hysol epoxy for wire sealant
PIN DESCRIPTION
PIN
Red Wire
Black Wire
NAME
FUNCTION
IO
GND
1-Wire bus interface. Open drain, requires external pull-up resistor.
Ground Reference
iButton LOCATION WITHIN MODULE
Each DS1921G in the DS9108 module contains a memory tag marker to indicate its position in the assembly. The
position mark is a CRC16 validated packet starting on page 15 in the user memory. The memory image for ‘TOP’,
‘MIDDLE’, and ‘BOTTOM’:
Table 1. Memory Tag Description
TAG TYPE
TOP
MIDDLE
BOTTOM
ADDRESS
1E0h–1E3h
CONTENTS
(HEX)
01 54 FA 60
01 4D 3B AA
01 42 7B AE
DESCRIPTION
‘T’ in a CRC validated packet
‘M’ in a CRC validated packet
‘B’ in a CRC validated packet
2 of 3
Embedded System
京公网安备 11010802033920号
EEWORLD
