Enhanced resistance accuracy, ultra-low TCR, and long-term stability — metal film, wire wound, thin film chip, and MELF types with tolerances as tight as ±0.005% and TCR as low as 3 ppm/°C for measurement, calibration, and instrumentation.
±0.005%
Tightest Tolerance
1mΩ – 1GΩ
Resistance Range
Film, Wire etc.
Technologies
Technologies:
±0.005% Tolerance
l
TCR 3 ppm/°C
l
Metal Film
l
Thin Film Chip
What Is a Precision Resistor?
A practical overview for engineers and procurement teams evaluating resistive solutions.
A
precision
resistor is defined not by its power handling, but by its
accuracy.
While standard resistors might carry tolerances of ±5% or ±1%, precision resistors achieve tolerances of
±0.1% down to ±0.005%
— and crucially, they maintain that accuracy over time and across temperature. A low
TCR (Temperature Coefficient of Resistance)
ensures the resistance value stays stable as the component heats up in operation, which is critical in measurement and feedback circuits where resistance drift would translate directly into measurement error.
RARA offers precision resistors across four construction technologies.
Metal film
types (MFR, MFD, CSR MELF) provide excellent stability and low noise for general precision applications.
Thin film chip
types (AR, ARN, SM) offer SMD convenience with high accuracy down to ±0.01%.
Wire wound
types (AX, CE-CL-T, 5G10, 8G16, GG102) achieve the very tightest tolerances — as low as ±0.005% with TCR of just 3 ppm/°C — for calibration and reference standards.
High-power precision
types (RMF, RH/RHF, TNP10P) combine accuracy with usable power ratings for sensing and feedback in power circuits.
Long-term stability and low noise are also key specifications — RARA precision resistors are engineered for
extended load life, meaning their resistance values remain within specification over thousands of hours of operation, not just on the initial measurement.
Construction Technologies
-Thin film chip (AR, ARN, SM)
-Metal film leaded (MFR, MFD)
-MELF metal film (CSR)
-Precision wire wound (AX, CE-CL-T, 5G10, 8G16)
-High-power precision (RMF, RH/RHF, TNP10P)
Key Advantages
-Tolerance as tight as ±0.005%
-TCR as low as 3 ppm/°C
-Long-term stability under load
-Low noise construction
-STEP files available for major models
RARA precision resistors feature enhanced resistance accuracy, lower TCR, longer load life, and long-term stability — the most common applications include current and voltage measurement and voltage dividers.
Where RARA precision resistors are deployed in the field.
Current & Voltage Measurement
Precision resistors are the foundation of accurate current and voltage measurement — used in shunt resistor networks, voltage dividers, and Wheatstone bridge circuits where a 0.1% resistance error translates directly into a 0.1% measurement error. The AR thin film chip and MFR metal film series are widely used in instrumentation amplifier input networks.
Calibration Standards
The 5340 calibration resistor (±0.01%, 5 ppm/°C) and ultra-tight wire wound types (5G10, 8G16 at ±0.005%, 3 ppm/°C) serve as reference resistance standards in calibration laboratories, metrology equipment, and secondary reference standards where traceability to national standards is required.
Feedback & Control Networks
Op-amp feedback networks, DAC output scaling, ADC reference dividers, and PID controller gain-setting networks rely on precision resistors to maintain accurate gain and offset values. Drift in these resistors causes gain error and offset drift — precision types with low TCR minimize this over temperature.
Medical Instrumentation
Patient monitoring equipment, infusion pumps, diagnostic analyzers, and imaging systems all require high-accuracy signal conditioning where resistance tolerance directly affects clinical measurement accuracy. The MFD (±0.02%, 5 ppm/°C) and ARN thin film types meet the stability demands of medical-grade designs.
Power Supply Feedback & Sensing
The RMF 4-terminal precision resistor (10W, ±0.1–5%, TCR 5–30 ppm/°C) and RH/RHF high-power wire wound series (1W–50W) bridge the gap between precision and power — used in current sensing, output voltage setting, and regulation feedback in power supplies and motor drives.
Defense & Aerospace
Avionics, guidance systems, and defense electronics demand resistors that maintain specification across extreme temperature ranges. Wire wound precision types (CE-CL-T, AX) with TCR of 5–15 ppm/°C and tolerances to ±0.01% provide the stability needed in mission-critical circuits operating from -55°C to +125°C.
Select models from our precision lineup. Download individual datasheets for full specifications, dimensions, and ordering codes.
Model: ARN
Resistor type: Power film precision
Description: Aluminum nitride, thin film, high precision chip
Supply Voltage: 200V
Power Rating: 0.5W~6W
Resistance (Ω): 50~30.1K
Tolerance (%): ±0.1, ±0.25, ±0.5, ±1
TCR (ppm/C): 25, 50
Model: AR
Resistor type: Precision
Description: High precision chip
Power Rating: 1/32W~1W
Resistance (Ω): 1~3M
Tolerance (%): ±0.01~±1
TCR (ppm/C): 5~50
Model: SM
Resistor type: Precision
Description: High precision chip
Power Rating: 1/8W~2W
Resistance (Ω): 500k~1G
Tolerance (%): ±0.1, ±0.25, ±0.25
TCR (ppm/C): 25, 50, 100
Model: CSR
Resistor type: Precision
Description: MELF, metal film
Power Rating: 1/4W~2W
Resistance (Ω): 1~10M
Tolerance (%): ±0.1~±5
TCR (ppm/C): 10~50
Model: MFR
Resistor type: Precision
Description: Leaded metal film
Power Rating: 1/8W~3W
Resistance (Ω): 1~10M
Tolerance (%): ±0.05~±1
TCR (ppm/C): 5~10
Model: MFD
Resistor type: High precision
Description: Leaded metal film
Power Rating: 1/4W, 1/2W
Resistance (Ω): 10~1M
Tolerance (%): ±0.02, ±0.05, ±0.1
TCR (ppm/C): 5~25
Model: AX
Resistor type: Precision
Description: Wire wound
Power Rating: 1W
Resistance (Ω): 1~400k
Tolerance (%): ±0.01, ±0.05, ±0.1
TCR (ppm/C): 10~15
Model: CE-CL-T
Resistor type: Precision
Description: Wire wound
Power Rating: 1/8W~1W
Resistance (Ω): 0.1~1.5M
Tolerance (%): ±0.01~±0.1
TCR (ppm/C): 5~90
Model: 5G10
Resistor type: Precision
Description: Wire wound
Power Rating: 0.2W
Resistance (Ω): 10~200k
Tolerance (%): ±0.01, ±0.1
TCR (ppm/C): 3
Model: 8G16, 8G24
Resistor type: Precision
Description: Wire wound
Power Rating: 0.33W
Resistance (Ω): 1~1M
Tolerance (%): ±0.005, ±0.01, ±0.1
TCR (ppm/C): 3
Model: GG102
Resistor type: Precision
Description: Wire wound
Power Rating: 0.3W
Resistance (Ω): 10~250k
Tolerance (%): ±0.01, ±0.1
TCR (ppm/C): 3
Model: TNP10P, TNP20P
Resistor type: Precision
Description: Power film
Power Rating: 10W
Resistance (Ω): 0.1~51k
Tolerance (%): ±0.05, ±1
TCR (ppm/C): 5, 10, 25
Model: RMF
Resistor type: Precision
Description: High power 4 terminal
Power Rating: 10W
Resistance (Ω): 0.5~200
Tolerance (%): ±0.1~±5
TCR (ppm/C): 5, 10, 15, 20, 30
Model: 400 Series
Resistor type: High Voltage
Description: Precision, Non-Inductive
Low TCR
Power Rating: 3.8W~20W
Supply voltage: 15kV~90kV
Resistance (Ω): 1k~1T
Tolerance (%): ±0.05 to ±10
TCR (ppm/C): 5, 10, 15, 25, 50, 100
Model: LM
Resistor type: High precision
Description: Plate
Power Rating: 1/8W-1W
Resistance (Ω): 500k~1G
Tolerance (%): ±0.1, ±0.25, ±0.50
TCR (ppm/C): 25, 50, 100
Model: RH/RHF
Resistor type: Precision
Description: High power wire wound
Power Rating: 1W~50W
Resistance (Ω): 1m~600k
Tolerance (%): ±0.01, ±1
TCR (ppm/C): 30, 50, 100
Model: 5340
Resistor type: Precision
Description: Calibration
Power Rating: 0.5W
Resistance (Ω): 1m~1k
Tolerance (%): ±0.01
TCR (ppm/C): 5
Why Choose RARA Precision Resistors
What sets RARA apart for engineers and procurement managers in industrial and automotive markets.
01
Extreme Accuracy
Tolerances as tight as ±0.005% and TCR as low as 3 ppm/°C — across metal film, thin film chip, wire wound, and MELF construction types to suit every precision circuit requirement.
02
Long-Term Stability
Precision resistors are only useful if they stay accurate. RARA precision types are engineered for extended load life — maintaining resistance within specification over thousands of hours of operation.
03
Full Technology Range
From 1/32W SMD thin film chips to 50W high-power precision wire wound types — one precision resistor family covering every power level and form factor from a single ISO-certified supplier.
04
Global Track Record
Trusted by Toshiba, Siemens, Rockwell, LG, and Schneider Electric — deployed in instrumentation, medical, and industrial measurement systems across six continents.
