Our Biomedical Chip Thermistor assemblies are
designed for use in applications involving both
intermittent and continuous patient temperature
monitoring. Repeatability and fast response are
essential not only for the intermittent temperature
requirements associated with oral and rectal fever
measurements, but also with the continuous
monitoring often necessary during induced-
hypothermia and general anesthesia, or when
employed in the care of infants and premature
babies. Intensive care units along with recovery
rooms have also adopted patient temperature
as part of their vital sign monitoring procedures.
Temperature monitoring for skin surface, tympanic,
esophageal, foley catheters and biofeedback
applications has also improved due to the high
stability and tight interchangeable tolerances
designed into each Thermometrics’ Biomedical
assembly.
NTC Type MA
Biomedical Chip
Thermistors
Applications
A complete line of standard sub-assemblies is
available. Continuous research and development
efforts within Thermometrics have resulted not only
in these eld proven designs, but in the development
of our Unitherm Thermochip Thermistor, designed
exclusively for biomedical applications in the range
of 32°F to 122°F (0°C to 50°C).
Although low in cost , these highly stable,
precision thermochips provide the reliability,
tight interchangeable tolerances, geometries,
and fast response times that are often required.
Thermometrics employs experienced applications
engineers who welcome inquiries, whether for
assistance, or to help with your design requirements
concerning new and existing applications.
Amphenol
Advanced Sensors
NTC Type MA Specifications
MA100
Designed for use in catheter assemblies, these sen-
sors
are available with nominal resistance values of
2252, 3000, 5000, and 10,000 Ω at 77°F (25°C).
Close monitoring of manufacturing processes allow
Thermometrics to maintain tight interchangeability
tolerances with volume production. Typical design
parameters are represented in Assembly Type table.
0.030 in (0.76 mm) (10 KΩ only) and 0.050
in(1.27mm) diameters available with kapton sleeve
only.
0.070 in (1.78 mm) diameter normally supplied with
molded plastic tip.
MA200
Intermittent body temperature measurements are
common practice in all phases of patient care. This
assembly is ideally suited for the disposable cover
oral and rectal fever thermometers in use today. It
features rugged construction with tip sensitive shaft
assemblies exhibiting resistance values of 2252,
3000, 5000, and
10,000 Ω at 77°F (25°C). Refer to Assembly Type
table for typical design parameters.
MA300
Routine continuous patient temperature monitor-
ing is now feasible by using the convenience of the
patient’s skin site as an indicator of body tempera-
ture. The stainless steel housing used is suitable for
both reusable and disposable applications, while
maintaining maximum patient comfort . Nominal re-
sistance values of 2252, 3000, 5000, and 10,000 Ω
at 77°F (25°C) are available. Refer to Assembly Type
table for typical design parameters.
Assembly Type
Assem-
bly Type MA100 MA200 MA300
Standard
Diameters
(D)
0.030 in (0.762
mm)
0.050 in (1.27 mm)
0.070 in (1.78 mm)
0.080 in (2.03 mm)
0.156 in (3.96 mm) 0.375 in (9.52 mm)
Body
Length (L)
3/8 in (9.52 mm) 3.75 in (95.25 mm) N/A
Standard
Lead
Length (A)
24 in (610mm)
36 in (914mm)
2 in (51 mm) 24 in (610mm)
Tolerance See Tolerance
Code and Tem-
perature Table
See Tolerance
Code and Tem-
perature Table
See Tolerance
Code and Tem-
perature Table
Wire Gauge 20, 30, 32, 38,
AWG
30 AWG 30 AWG
Standard
Wire
Insulation
*Heavy Isomid
*Medical Grade
PVC
*Polyurethane with
Nylon Overcoat
PTFE Medical Grade
PVC
PTFE
Body
Material
Molded Plastic or
Kapton Sleeve
Lexan Shaft
Aluminum Tip
Stainless Steel
Nominal R Values @ 77°F
(25°C)
2252 Ω, 3000 Ω, 5000 Ω, 10,000 Ω
(for all three types)
Thermal Response Time (63% Response)
Series Still Air Still Water*
MA100
Catherter Assembly
15 seconds 2.0 seconds
MA200
Oral-Rectal Assembly
35 seconds 0.6 seconds
MA300
Skin Surface Assembly
45 seconds 2.0 seconds
*Response time provided is for assembly plunged from 77°F (25°C) air to 41°F (5°C) water.
NTC Type MA Specifications
Tolerance Code and Temperature Range
Tolerance Code
Temperature
Range °F (°C)
A
±°F (±°C)
B
±°F (±°C)
C
±°F (±°C)
32 to 68 (0 to 20) 0.27 (0.15) 0.36 (0.2) 0.45
(0.25)
68 to 95 (20 to 35) 0.18 (0.1) 0.27 (0.15) 0.36 (0.2)
95 to 102 (35 to 39) 0.09 (0.05) 0.18 (0.1) 0.27
(0.15)
102 to 107.60 (39
to 42) 0.14 (0.075 0.27 (0.15) 0.36 (0.2)
107.60 to 113 (42
to 45) 0.18 (0.1) 0.27 (0.15) 0.36 (0.2)
113 to 122 (45 to 50) 0.27 (0.15) 0.36 (0.2) 0.45
(0.25)
Data
Our biomedical series thermistor chips and
sub-assemblies are designed to be interchange-
able over a 32°F to 122°F (0°C to 50°C) range. Best
overall stability is maintained when exposure and
storage temperatures remain below 158°F (70°C).
Temperature
°F (°C) 2252 Ω 3 kΩ 5 kΩ 10 kΩ 103(Y) Ω
32.00 (0) 7373.00 9821.93 16369.9 32739.8 29565.8
33.80 (1) 7005.80 9332.76 15554.6 31109.2 28224.8
35.60 (2) 6659.04 8870.84 14784.7 29569.5 26951.9
37.40 (3) 6331.49 8434.49 14057.5 28115.0 25743.3
39.20 (4) 6021.97 8022.17 13370.3 26740.6 24595.5
41.00 (5) 5729.40 7632.41 12720.7 25441.4 23505.0
42.80 (6) 5452.74 7263.87 12106.4 24212.9 22468.7
44.60 (7) 5191.06 6915.27 11525.4 23050.9 21483.8
46.40 (8) 4943.46 6585.43 10975.7 21951.4 20547.2
48.20 (9) 4709.11 6273.23 10455.4 20910.8 19656.6
50.00 (10) 4487.22 5977.64 9962.74 19925.5 18809.3
51.80 (11) 4277.07 5697.69 9496.15 18992.3 18003.1
53.60 (12) 4077.97 5432.47 9054.11 18108.2 17235.7
55.40 (13) 3889.29 5181.11 8635.19 17270.4 16505.1
57.20 (14) 3710.42 4942.83 8238.05 16476.1 15809.4
59.00 (15) 3540.80 4716.88 7861.46 15722.9 15146.7
60.80 (16) 3379.91 4502.54 7504.24 15008.5 14515.3
62.60 (17) 3227.24 4299.17 7165.28 14330.6 13913.6
64.40 (18) 3082.34 4106.14 6843.57 13687.1 13340.0
66.20 (19) 2944.77 3922.88 6538.13 13076.3 12793.0
68.00 (20) 2814.12 3748.83 6248.05 12496.1 12271.4
69.80 (21) 2690.01 3583.49 5972.48 11945.0 11773.8
71.60 (22) 2572.07 3426.38 5710.63 11421.3 11299.0
73.40 (23) 2459.96 3277.03 5461.72 10923.4 10845.8
75.20 (24) 2353.37 3135.04 5225.07 10450.1 10413.1
77.00 (25) 2252.00 3000.00 5000.00 10000.0 10000.0
78.80 (26) 2155.56 2871.53 4785.88 9571.77 9605.42
80.60 (27) 2063.79 2749.28 4582.13 9164.26 9228.45
82.40 (28) 1976.44 2632.91 4388.19 8776.38 8868.24
84.20 (29) 1893.27 2522.12 4203.54 8407.07 8523.96
86.00 (30) 1814.07 2416.61 4027.68 8055.35 8194.82
87.80 (31) 1738.61 2316.09 3860.15 7720.30 7880.09
89.60 (32) 1666.71 2220.31 3700.51 7401.03 7579.07
91.40 (33) 1598.18 2129.02 3548.36 7096.72 7291.10
93.20 (34) 1532.85 2041.98 3403.30 6806.60 7015.55
95.00 (35) 1470.54 1958.98 3264.97 6529.94 6751.83
96.80 (36) 1411.11 1879.81 3133.02 6266.03 6499.37
98.60 (37) 1354.41 1804.27 3007.12 6014.23 6257.64
100.40 (38) 1300.29 1732.18 2886.96 5773.93 6026.13
102.20 (39) 1248.63 1663.36 2772.27 5544.53 5804.36
104.00 (40) 1199.30 1597.65 2662.75 5325.50 5591.88
105.80 (41) 1152.19 1534.89 2558.15 5116.30 5388.26
107.60 (42) 1107.19 1474.94 2458.23 4916.46 5193.09
109.40 (43) 1064.18 1417.65 2362.75 4725.49 5005.96
111.20 (44) 1023.08 1362.89 2271.49 4542.98 4826.53
113.00 (45) 983.78 1310.55 2184.24 4368.49 4654.43
114.80 (46) 946.21 1260.49 2100.82 4201.64 4489.33
116.60 (47) 910.27 1212.62 2021.03 4042.05 4330.91
118.40 (48) 875.89 1166.81 1944.69 3889.38 4178.88
120.20 (49) 842.99 1122.99 1871.65 3743.29 4032.94
122.00 (50) 811.50 1081.04 1801.73 3603.46 3892.83
Resistance vs Temperature
AAS-920-321C - 02/2020
www.amphenol-sensors.com
© 2020 Amphenol Corporation. All Rights Reserved. Specications are subject to change without notice.
Other company names and product names used in this document are the registered trademarks or
trademarks of their respective owners.
Amphenol
Advanced Sensors
NTC Type MA Specifications
Ordering Information
The code number to be ordered may be specif ied as follows:
MA
Code Standard Assemblies
100FA Series 100, 0.070 in (1.78 mm) diameter molded plastic tip,
30 gauge PVC insulated ribbon cable.
100FD Series 100, 0.070 in (1.78 mm) diameter molded plastic tip,
32 gauge bilar heavy isomid insulation.
100DD Series 100, 0.050 in (1.27 mm) diameter kapton sleeve with
32 gauge bilar heavy isomid insulation.
100BF Series 100, 0.030 in (0.768 mm) diameter kapton sleeve with
38 gauge bilar heavy isomid insulation.
200LC Series 200, 0.156 in (3.96 mm) diameter aluminum tip,
30 gauge PTFE leads.
300TA Series 300, 0.375 in (9.52 mm) diameter stainless steel cup,
30 gauge PVC insulated ribbon cable.
300TB Series 300, 0.375 in (9.52 mm) diameter stainless steel cup,
30 gauge PTFE insulated ribbon cable.
100GG Series 100, 0.080 in (2.03 mm) diameter molded plastic tip,
28 gauge kynar insulated twisted pair.
Code Resistance Cable*
232 2252 Ω
302 3000 Ω
502 5000 Ω
103 10,000 Ω
103 (Y) 10,000 Ω
Code Tolerance
X Refer to tolerance code and temperature
range table
MA - ______ - ______ - ______ Typical Model Number
*Refer to resistance vs temperature table on previous page.