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CHARACTERISTICS
TDH Series
35 Watt DPAK Package
Thick Film Power Surface Mount
Terminal Copper
Terminal Plating Terminals- SnAg,
Thermal Header- German Silver/Nickel Silver
Resistance Range 0.05Ω to 10KΩ other values on request
Tolerance ±1% to ±10% (0.5% on request)
Max. Operating Voltage 350V
Insulation Resistance 10GΩ min.
Power Rating Depends upon case temperature. See der-
ating curve.
DPAK style power package for surface
mounting applications; 35W power rating at
25°C case temperature.
Working Temperature
Range
-55°C to +175°C
Solder Process The TDH35P cannot exceed 215°C (260°C
for the TDH35H) for more than 10 seconds
during soldering process.
Derating 100% @ 25°C to 0% @ 150°C curve refer-
enced to case temperature
Dielectric Strength 1,800VAC
Operating Temperature
Range
-55°C to +150°C
Temperature Coefficient 10Ω and above, ±50ppm/°C, referenced to
25°C, ∆R taken at +105°C. Between 1 and
10Ω, ±(100ppm+0.002Ω)/°C, referenced to
25°C, ∆R taken at +105°C. For under 10Ω:
0R6 - 9R9: 100PPM
0R4 - 0R59: 150PPM
0R2 - 0R39: 250PPM
0R1 - 0R19: 500PPM
0R05 - 0R09: 1000PPM
Inductance less than 20 nanohenries
Flatness less than 0.1mm tolerance
Test Condition Result
Load Life MIL–R–39009, 2,000 hours ∆R ±(1.0%
+0.01Ω)
Moisture
Resistance
MIL–Std–202, Method 106 ∆R =(0.5%
+0.01Ω) max.
Short Time
Overload
2 times rated power with
applied voltage not to exceed
1.5 times maximum continu-
ous operating voltage for 5
seconds
∆R ±(0.3%
+0.01Ω) max.
Thermal Shock MIL–Std–202, Method 107,
Cond. F
∆R =(0.3%
+0.01Ω) max.
Terminal
Strength
MIL–Std–202, Method 211,
Cond. A (Pull Test) 2.4N
∆R =(0.2%
+0.01Ω) max.
Vibration, High
Frequency
MIL-Std-202, Method 204,
Cond. D
ΔR =(0.2%
+0.01Ω) max.
Ohmite’s TDH resistor is an economi-
cal solution to intermediate power
application design requirements.
TDH’s reliable thick film on alumina
substrate construction can be easily
heat sinked for higher power perfor-
mance. TDH resistors are ideal for
pulse-loading, pre-charge, bleeder,
and snubber applications.
FEATURES
•35Wattpowerratingat25°C
•SMD-DPAKpackageconfigu-
ration
•Heatresistancetocooling
plate:Rth<4.28°C/W
•Amoldedcaseforenviron-
mental protection.
•Resistorelementiselectrically
insulated from the metal sink
tab.
Soldering note: During surface mount soldering the soldering
temperature profile must not cause the metal tab of this device to
exceed 220°C (260°C for the TDH35H)!
Derating
100
Percent Rated Power
Bottom of base plate Temperature, °C
60
20
0
050 10025 75 125
80
40
150 175
35
21
7
0
28
14
Rated Power, W
Derating(thermalresistance):0.23W/°C(4.28°C/W).The
case temperature is to be used for purposes of establishing
the applied power limit. The case temperature measurement
must be made with a thermocouple contacting the center of
the component mounted on the designed heat sink. Thermal
grease should be applied propperly.
(continued)