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CHARACTERISTICS
TCH Series
35 Watt TO220 Package Thick Film Power
Resistance Range
0.05Ω to 10KΩ (higher values on request sub-
ject to derating)
Resistance
Tolerance:
± 5% standard; ± 1% available on request
Temperature
Coefficient
Referenced to 25°C, ∆R taken at +105°C
10Ω and above: ±50 ppm°C
For under 10Ω:
0R6 - 9R9: 100PPM
0R4 - 0R59: 150PPM
0R2 - 0R39: 250PPM
0R1 - 0R19: 500PPM
0R05 - 0R09: 1000PPM
Max. Operating
Voltage
350V
Dielectric Strength
1800 VAC
Insulation
Resistance
10GΩ min.
Momentary
Overload
2x rated power for 5 seconds as long as the
applied voltage ≤1.5 times the continuous
operating voltage, where ∆R ±(0.3% + 0.01Ω)
max
Terminal Material
Copper
Terminal Plating
Lead Free Solder (97% Tin, 3% Silver)
Maximum Torque
0.9 Nm
Power Rating
35 Watts @ 25°C case temperature; see derat-
ing curve, below
Working
Temperature
Range
-55°C to +175°C
Solder Process
The TCH35 cannot exceed 260°C for more
than 10 seconds during soldering process
Test Condition Result ∆R
Load Life
MIL-R-39009, 2000 Hours
@ Rated Pwr
±(1.0% +0.01) Ω
Thermal
Shock
MIL-R-STD-202, Method
107, Cond. F
±(0.3% +0.01) Ω max
High Freq
Vibration
MIL-R-STD-202, Method
204, Cond. D
±(0.2% +0.01) Ω max
Terminal
Strength
MIL-R-STD-202, Method
211, Cond. A (Pull Test)
2.4N
±(0.2% +0.01) Ω max
Moisture
Resistance
MIL-R-STD-202, Method
106
± (0.5% +0.01) Ω max
175
100
Percent Rated Power
Bottom of base plate Temperature, °C
60
20
0
050 100 15025 75 125
80
40
Rated Power, Watts
20/35
16/28
12/21
8/14
4/ 7
0
TAH/TCH
TCH
TAH
Ohmite’s TCH35 TO220 package
resistor provides 35W of steady state
power when properly used in today’s
well defined heat sink applications.
These very low induction resistors
are built under proprietary processes
that deliver more power handling
capability than other TO220 package
resistors of similar size.
Standard terminal forms are provid-
ed for manual or automatic insertion.
A single screw mounting tab con-
nects to the heat sink and should be
accompanied by the use of a thermal
compound. The TCH35 Series offers a
low thermal resistance to the heat sink
of <4.28°C/W.
FEATURES
• 35W Power Rating @ 25°C
• Very Low Inductance Design
• Single Screw Mounting
• Low Thermal Resistance to
Heat Sink @ RTH<4.28°C/W
• Resistance Element is
Electrically Insulated from
Metal Heat Sink Mounting Tab
APPLICATIONS
• Switching Power Supplies
• Snubbers
• High Frequency
• Voltage Regulation
• Low Energy Pulse Loading
Derating
(continued)
