RS Series Thick Film Chip Current Sensing Resistors
Thick film resistive element on ceramic substrate
Power rating 1/16W to 2W
Resistance range 10mΩ to 976mΩ
Low milliohm values suited to series-connected current shunt measurement
Tolerance options ±1% and ±5%
TCR options 200 ppm/°C and 1500 ppm/°C
Surface mount chip package for automated PCB assembly
Compact footprint for high-density board layouts
What are the RS Series Thick Film Chip Current Sensing Resistors?
The RS is a surface-mount thick film chip resistor optimised for current sensing applications, covering the milliohm resistance range most commonly required when a shunt element is placed in series with a load circuit. Using a thick film resistive element deposited on a ceramic substrate, the series delivers the combination of low resistance, manageable power dissipation, and practical SMD packaging that current measurement circuits demand. Power ratings extend from 1/16W up to 2W depending on case size, providing coverage from compact low-power signal monitoring applications through to moderate-current industrial measurement loops.
Resistance values span 10mΩ to 976mΩ, concentrating on the sub-ohm range where a series shunt produces a measurable voltage drop proportional to current without imposing significant power loss or voltage drop on the load circuit itself. Tolerance options of ±1% and ±5% allow designers to select the appropriate balance between measurement accuracy and component cost. TCR is offered at 200 ppm/°C and 1500 ppm/°C — the tighter 200 ppm/°C grade is preferred for applications where the component self-heats appreciably under sustained load, and where resistance drift with temperature would otherwise introduce a systematic current measurement error. The 1500 ppm/°C grade suits lower-accuracy or intermittent-duty applications where cost is the primary design constraint.
The thick film construction uses a resistive paste fired onto the ceramic substrate, producing a planar element with inherently low inductance compared to wirewound alternatives. This makes the RS series compatible with switching and pulse-width-modulated circuits where a wirewound shunt would introduce reactive impedance errors. The SMD chip format allows the RS to be placed directly in the current path on the PCB using standard automated pick-and-place assembly, with no special tooling or handling beyond normal ESD precautions. The compact package footprint suits high-density board layouts where space for the current measurement element is constrained by surrounding power or signal components.
The RS series covers the general-purpose end of the thick film chip current sensing category, offering an accessible milliohm resistance range and straightforward surface mount integration for the broad range of industrial, consumer, and power electronics applications that require basic current measurement without the cost and complexity of precision shunt alternatives.
RS Series Thick Film Chip Current Sensing Resistors Specifications
A practical overview for engineers and procurement teams evaluating resistive solutions.
Model: RS
Resistor type: Current sensing
Description: Thick film chip
Power Rating: 1/16W~2W
Resistance (Ω): 10m~976m
Tolerance (%): ±1, ±5
TCR (ppm/C): 200, 1500
Applications of the RS Series Thick Film Chip Current Sensing Resistors
Where RARA metal clad resistors are deployed in the field.
Switch-mode power supplies and DC-DC converters — output current monitoring and current-mode control loops where a low-resistance series shunt is placed in the power path to generate a feedback signal proportional to load current for regulation and overcurrent detection.
Motor drive and variable-speed drive circuits — phase current sensing in brushed and brushless DC motor controllers, where the RS chip shunt provides the current feedback signal for torque control, speed regulation, and overload protection.
Battery charging and management systems — charge and discharge current monitoring in portable device chargers, power banks, and battery management units, where a compact milliohm shunt is needed in a space-constrained PCB layout alongside the charging IC.
UPS and power conditioning equipment — load current sensing in uninterruptible power supply systems and power conditioners, providing the measurement signal for overload alarms and output regulation feedback.
Industrial automation and control panels — current monitoring in PLC output modules, relay driver stages, and embedded industrial controllers where a surface-mount current sense element is required within a compact board design.
LED driver circuits and lighting controls — output current sensing in constant-current LED drivers and dimmable lighting systems, where the thick film chip shunt provides the feedback signal that maintains consistent LED current independent of forward voltage variation.
Consumer electronics and portable devices — current measurement in USB power delivery circuits, laptop adapters, and handheld device power management stages, where the SMD package and sub-2W power rating suit the compact board layouts typical of consumer product designs.
Telecommunications power equipment — current monitoring in DC power distribution units, rectifier modules, and base station power supplies, providing overcurrent detection and load balancing feedback in rack-mounted power infrastructure.
Test and measurement instruments — shunt elements in benchtop power supplies, electronic loads, and current measurement accessories where a calibrated milliohm resistance in a stable chip package provides a convenient and repeatable current sensing reference.
Related Products of the RS Series Thick Film Chip Current Sensing Resistors
Model: CS
Resistor type: Current sensing
Description: Chip
Power Rating: 1/20W~3W
Resistance (Ω): 1m~8000m
Tolerance (%): ±1, ±2, ±5
TCR (ppm/C): 100, 1000
Model: CSTN
Resistor type: Current sensing
Description: Chip
Power Rating: 1/16W~3W
Resistance (Ω): 50m~1000m
Tolerance (%): ±0.5, ±1
TCR (ppm/C): 50, 100, 200
Model: RTX
Resistor type: Current Sensing
Description: Chip
Power Rating: 1/8W~2W
Resistance (Ω): 50m~1000m
Tolerance (%): ±0.5, ±1, ±2, ±5
TCR (ppm/C): 75-300
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.
