High-precision film resistors rated from 10W to 2000W — delivering tight tolerances, low TCR, and high power density in compact chassis-mount, SMD, and water-cooled formats for demanding industrial and high-frequency applications.
0.02Ω – 500MΩ
Resistance Range
25 ppm/°C
Best TCR Available
Certifications:
AEC-Q200
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ISO9001
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IATF16949
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UL Listed
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Laser Trimmed
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TÜV
What is a Power Film Resistor?
A practical overview for engineers and procurement teams evaluating resistive solutions.
A
power film
resistor is made by depositing a thin or thick layer of resistive material — typically a metal alloy or carbon compound — onto a ceramic or aluminum nitride substrate. Unlike wire wound resistors, the film deposition process is extremely accurate, producing
very tight tolerances and low temperature coefficient of resistance (TCR)
values that are difficult to achieve with wound construction.
This precision makes power film resistors the preferred choice when
accuracy and stability under temperature change
are critical — such as in medical equipment, test instrumentation, laser power supplies, and RF/telecom systems. Many RARA models can also be
laser trimmed after manufacture
for even greater precision, achieving tolerances as tight as ±0.1%.
RARA's power film range spans from compact
SMD chip resistors at 2W
to massive
planar chassis-mount units rated at 2000W, including water-cooled models for the most demanding thermal environments. Aluminum nitride substrate variants offer exceptional thermal conductivity for high-density designs.
Construction
-Thin film on ceramic substrate
-Thick film on ceramic substrate
-Aluminum nitride (AlN) chip
-Carbon film MELF
-Water-cooled planar construction
Key Advantages
-Very tight tolerances — down to ±0.1%
-Low TCR — as low as 25 ppm/°C
-Laser trimmable for extra precision
-High power density in small footprint
-STEP files available for thermal simulation
Power film resistors are the components you want when you need high power with limited space — the film deposition process delivers accuracy that wire wound construction simply cannot match.
Where RARA power film resistors are deployed in the field.
Medical & Test Equipment
The tight tolerances and stable TCR of film resistors make them essential in medical imaging, laboratory instruments, and precision test equipment — where resistance drift caused by temperature change would affect measurement accuracy.
Telecom & RF Systems
Power film resistors are used as termination resistors, dummy loads, and attenuator components in RF and telecom base stations, where low inductance and flat frequency response are critical. The HPR series supports supply voltages up to 8kV.
Laser Power Supplies
High-power laser systems require stable, accurate load resistors for current control and energy discharge. The HPR planar series at up to 2000W and the RQO capacitor discharge model are purpose-built for pulsed and continuous laser power applications.
Power Supplies & Inverters
Used as snubber resistors, bleed resistors, and feedback network components in switch-mode power supplies, solar inverters, and industrial UPS systems — where low TCR ensures stable regulation across the full operating temperature range.
Water-Cooled Industrial Systems
The WCR water-cooled series (500W–1000W) is designed for high-duty-cycle industrial processes where convection cooling alone is insufficient — including plasma systems, induction heaters, and high-current test rigs.
High-Density PCB Designs
SMD chip variants (SMF, ARN, CRP, TNP) allow engineers to place significant power dissipation capability directly on the PCB — reducing board area requirements in compact power electronics, EV battery management systems, and industrial controllers.
Select models from our power film lineup. Download individual datasheets for full specifications, dimensions, and ordering codes.
Model: HPR
Resistor type: Planar ultra high power
Description: Chassis Mounted
Power Rating: 1000, 1400, 2000W
Supply Voltage: 8kV
Resistance (Ω): 1~100k
Tolerance (%): ±1, ±5, ±10
TCR (ppm/C): 100
Model: TPK600, TPK900
Resistor type: Power film
Description: Chassis mounted
Power Rating: 600W, 900W
Resistance (Ω): 10~1.6k
Tolerance (%): ±5
TCR (ppm/C): 50
Model: TPU
Resistor type: Power film
Description: Chassis mounted
Power Rating: 300W, 600W, 800W
Resistance (Ω): 4.7~500M
Tolerance (%): ±1, ±2, ±5, ±10
TCR (ppm/C): 50-250.
Model: TPM150~600
Resistor type: Power film
Description: Chassis mounted
Power Rating: 150W~600W
Resistance (Ω): 0.1~1M
Tolerance (%): ±5
TCR (ppm/C): 100
Model: TPX600L
Resistor type: Power film
Description: Chassis mounted
Power Rating: 600W
Resistance (Ω): 10~1k
Tolerance (%): ±5
TCR (ppm/C): 50
Model: TPK900L
Resistor type: Power film
Description: Chassis mounted
Power Rating: 900W
Resistance (Ω): 25~1k
Tolerance (%): ±5
TCR (ppm/C): 50
Model: TNP10/20S/50U
Resistor type: Power film
Description: Power thin film
Power Rating: 20W, 35W, 50W
Resistance (Ω): 0.02~510k
Tolerance (%): ±1, ±5
TCR (ppm/C): 50, 100, 250
Model: TNP50S, TNP100S
Resistor type: Power film
Description: Power thin film, TO227
Power Rating: 50W, 100W
Resistance (Ω): 0.02~510k
Tolerance (%): ±1, ±5
TCR (ppm/C): 50, 100, 250.
Model: RTS-01
Resistor type: Power film
Description: Heatsinkable thick film
Power Rating: 100W
Resistance (Ω): 0.1~1M
Tolerance (%): ±5, ±10
TCR (ppm/C): 100
Model: RTS-02
Resistor type: Power film
Description: Heatsinkable thick film
Power Rating: 300W, 600W
Resistance (Ω): 0.1~1M
Tolerance (%): ±5, ±10
TCR (ppm/C): 100.
Model: TNP25, TNP45
Resistor type: Power film
Description: SMD surge protection
Power Rating: 25W, 45W
Resistance (Ω): 0.1~51k
Tolerance (%): ±1
TCR (ppm/C): 100
Model: RQO
Resistor type: Power film
Description: High power capacitor discharge
Power Rating: 10W
Resistance (Ω): 0.5~75k
Tolerance (%): ±5, ±10
TCR (ppm/C): 490 max.
Model: CFS
Resistor type: Power film
Description: Carbon film, MELF
Power Rating: 1/4W~2W
Resistance (Ω): 1~1M
Tolerance (%): ±2, ±5
TCR (ppm/C): 350~1000
Model: SMF
Resistor type: Power film
Description: Chip
Power Rating: 2W, 3W, 5W
Resistance (Ω): 10~20M
Tolerance (%): ±1, ±5
TCR (ppm/C): 100
Model: ARN
Resistor type: Aluminum nitride
Description: Chip
Power Rating: 1/2W, 1W, 2W, 6W
Resistance (Ω): 50~30.1k
Tolerance (%): ±0.1
TCR (ppm/C): 25, 50
Model: CRP
Resistor type: Aluminum nitride
Description: Chip
Power Rating: 2.4W, 3.5W
Resistance (Ω): 10~2k
Tolerance (%): ±1, ±5
TCR (ppm/C): 150
Model: HPF250
Resistor type: Power film
Description: Power thick film
Power Rating: 250W
Resistance (Ω): 5~1k
Tolerance (%): ±10
TCR (ppm/C): 250
Model: WCR
Resistor type: Power film
Description: Water cooled
Power Rating: 500W, 1000W
Resistance (Ω): 5~1k
Tolerance (%): ±10
TCR (ppm/C): 250
Why Choose RARA Power Film Resistors
What sets RARA apart for engineers and procurement managers in industrial and automotive markets.
01
Precision Film Deposition
Accurate resistive film deposition yields tight tolerances down to ±0.1% and TCR as low as 25 ppm/°C — performance that wire wound construction cannot match.
02
Laser Trimmable
Many models can be laser trimmed post-manufacture for increased precision, making them suitable for calibration-critical applications in medical and test instrumentation.
03
Broadest Power Range
From 2W SMD chips to 2000W planar units and water-cooled models — a complete film resistor family sourced from a single ISO9001 and IATF16949 certified supplier.
04
Global Track Record
Trusted by Siemens, Rockwell, Toshiba, Schneider Electric, LG, and Hanwha — a customer list built on decades of consistent, certified performance.
