BWR05 Series High Precision Shunt Resistors
Precision resistive alloy element welded by specialist electron beam welding equipment
Resistance range 1.0mΩ to 5.0mΩ
Power rating 3W to 7W at 70°C depending on resistance value
Maximum operating current up to 83A (1.0mΩ variant)
Tolerance options ±0.5%, ±1.0%, and ±5.0%
TCR ≤75ppm/°C (1mΩ–2mΩ) and ≤50ppm/°C (3mΩ–5mΩ)
Operating temperature range −55°C to +170°C
AEC-Q200 qualified — suitable for automotive applications
RoHS compliant
Tape and reel packaging, 1200 pieces per reel
What are the BWR05 Series High Precision Shunt Resistors?
The BWR05 is a high-precision chip shunt resistor designed for accurate current sensing in demanding power electronics applications. Built on a precision resistive alloy and joined by electron beam welding technology that is independently designed and manufactured by C&B Electronics, the BWR05 achieves a maximum post-stamping tolerance of ±0.5% without any trimming step. This combination of controlled alloy composition, precision mechanical processing, and consistent welding quality delivers measurement accuracy that conventional thick film shunt resistors cannot match at equivalent resistance values.
The resistance range spans 1.0mΩ to 5.0mΩ, covering the low-impedance current sensing requirements of high-current power conversion and motor drive circuits. Power ratings scale with resistance from 7W at 1.0mΩ down to 3W at 5.0mΩ, all referenced to a terminal temperature of 70°C. Maximum operating currents range from 83A at the lowest resistance value to 24A at the highest. TCR is held to ≤75ppm/°C across the 1mΩ to 2mΩ range and to ≤50ppm/°C across the 3mΩ to 5mΩ range, measured between +20°C and +120°C, ensuring that sensing accuracy is preserved across the full thermal operating range of the application.
The BWR05 is qualified to AEC-Q200 and covers an operating temperature range of −55°C to +170°C, confirming suitability for automotive-grade designs as well as industrial power systems. Environmental stress testing demonstrates stable performance through 1000 hours of high-temperature exposure at 170°C, 1000 thermal shock cycles between −55°C and +155°C, and 2000-hour load life at rated power. Mechanical robustness is confirmed by half-sine shock testing at 100g peak acceleration and vibration testing across 10Hz to 2kHz. The component is supplied in tape and reel format at 1200 pieces per reel, compatible with standard SMT assembly processes using Sn-Ag-Cu reflow solder profiles. It is noted that the BWR05 is intended for DC and low-frequency sampling circuits only and is not recommended for high-frequency AC current sensing.
BWR05 Series High Precision Shunt Resistors Specifications
A practical overview for engineers and procurement teams evaluating resistive solutions.
Model: BWR05
Resistor type: Current sensing
Description: AEC-Q200 Chip Shunt
Power Rating: 3W~7W
Resistance (Ω): 1m~5m
Tolerance (%): ±0.5, ±1, ±5
TCR (ppm/C): 50, 75
Applications of the BWR05 Series High Precision Shunt Resistors
Where RARA current sensing resistors are deployed in the field.
Battery management systems — cell and pack current monitoring in EV and energy storage
Automotive DC-DC converters and on-board chargers — AEC-Q200 qualified current sensing
Motor drive and variable-speed drive circuits — phase current measurement and overcurrent detection
Solar and wind inverters — DC bus and string current sensing for MPPT and protection
Industrial power supplies and UPS — output current monitoring and load sharing
Power conversion and switching regulator circuits — inductor current sensing for control loops
Servo and traction inverters — high-current measurement in power stage feedback paths
Telecommunications power equipment — battery backup and rectifier current monitoring
Test and measurement instruments — precision current reference and calibration shunts
Consumer power electronics — high-current charger and adapter current sensing
Related Products of the BWR05 Series High Precision Shunt Resistors
Model: BWB
Resistor type: AEC-Q200
Description: Shunt
Power Rating: 2W~12W
Resistance (Ω): 0.2~5m
Tolerance (%): ±1, ±2, ±5
TCR (ppm/C): 50
Model: BWN
Resistor type: AEC-Q200
Description: Shunt
Power Rating: 2W~5W
Resistance (Ω): 2m~30m
Tolerance (%): ±1, ±2, ±5
TCR (ppm/C): 100 max.
Model: TCS
Resistor type: AEC-Q200 E-beam
Description: Shunt
Power Rating: 12W~36W
Rated Current: 200~350A
Resistance (Ω): 0.05~0.5m
Tolerance (%): ±1, ±2, ±5
TCR (ppm/C): 100
Model: BWR
Resistor type: AEC-Q200
Description: Shunt
Power Rating: 4W, 5W
Resistance (Ω): 0.3~3m
Tolerance (%): ±1, ±2, ±5
TCR (ppm/C): 50 max.
Why Choose RARA Current Sensing Resistors
What sets RARA apart for engineers and procurement managers in industrial and automotive markets.
01
8 Sub-Categories
No other single supplier covers AEC-Q200 chip shunts, milliohm precision types, four-terminal Kelvin shunts, power metering, and 12,000A panel shunts under one ISO-certified roof.
02
Extreme Precision
HPS, UHPS, and PSS precision shunts deliver ±0.05% tolerance and 3 ppm/°C TCR — meeting the accuracy demands of EV battery coulomb counting, precision power analyzers, and billing-grade energy metering.
03
Automotive Qualified
Multiple AEC-Q200 certified models (BCS, LRA, ECS, BWR, TCS, PCBS) with IATF 16949 manufacturing certification — covering EV battery management, motor control, and charging applications.
04
Global Track Record
Trusted by Tesla, GM Korea, Proterra, Siemens, Rockwell, and Schneider Electric — deployed in EV powertrains, industrial drives, and utility metering systems across six continents.
