Electronic Components and Resistors KOA / KOA Speer Electronics

Technical engineering catalog of KOA / KOA Speer Electronics passive components: precision chip resistors, power shunts, thermal sensors, and surge varistors.

KOA / KOA Speer Electronics: global engineering leader in passive electronic components

KOA Corporation and its affiliate KOA Speer Electronics manufacture an extensive line of surface mount resistors, current sensing shunts, and circuit protection devices. Fabrication facilities in Japan and the USA operate under IATF 16949 and ISO 9001 quality management guidelines.

Corporate heritage dating from 1940 and foundation of KOA Speer Electronics in 1980
Monthly volume of billions of passive components for automotive and industrial sectors
North American headquarters and distribution operations located in Bradford Pennsylvania
Quality 1st initiative recognized with multiple prestigious customer excellence awards

Low-resistance current sense shunts and power resistors series TLR, PS, UR

KOA Speer current sensing shunts are engineered for power conversion, traction drives, and battery management platforms. Solid metal plate elements and four-terminal Kelvin connections provide ultra-low parasitic inductance, excellent surge handling, and remarkable thermal stability.

Precision solid metal element TLR series resistors with resistance down to 0.5 mOhm
High power current detection components of PS family rated for dissipation up to 10W
Four-terminal Kelvin connection layout eliminating contact resistance measurement errors
Ultra-low temperature coefficient of resistance ensuring superior current reading precision

Anti-sulfur thick film chip resistors series RK73-RT and SG73-RT

KOA Speer anti-sulfur resistors are engineered for continuous operation in environments containing airborne sulfur compounds. Special alloy barrier terminations prevent hydrogen sulfide penetration into inner electrode layers, avoiding open circuit failures under harsh industrial conditions.

Specialized barrier electrode chemistry preventing silver sulfide crystal growth
Validated against rigorous ASTM B809 sulfur vapor standards without parameter drift
Surge resistant SG73-RT configurations designed for circuits facing severe pulse spikes
Extended operating temperature range rated from -55 up to +155 degrees Celsius

High voltage and surge pulse chip resistors series HV73, HV73V, RCR

KOA Speer high voltage resistors feature tailored resistive element geometry that minimizes electric field concentration. Capable of handling continuous working potentials up to 3 kV and high surge pulses, these components are widely deployed across industrial power supplies and medical systems.

Continuous working voltage ratings up to 3000V in compact surface mount packages
Optimized serpentine resistive pattern designed to prevent micro-arc breakdown failures
Through-hole leaded high voltage RCR components with robust protective dielectric coating
Full qualification according to automotive AEC-Q200 passive stress test requirements

Precision thin film chip resistors series RN73R and RN73H

KOA Speer RN73R precision thin film resistors utilize sputtered metal film technology for exceptional accuracy. With tolerances down to ±0.05% and temperature coefficients to ±5 ppm/°C, they deliver superior electrical stability and moisture resistance in analog instrumentation.

Ultra-tight resistance tolerance down to ±0.05% for critical analog instrumentation
Temperature coefficient of resistance as low as ±5 ppm/°C over wide operating range
Advanced inorganic passivation layer providing superior long-term moisture endurance
Extremely low current noise profile optimal for sensitive instrumentation amplifiers

Platinum thermal sensors SDT73 and circuit protection varistors NV73S

KOA Speer thermal sensors and circuit protection portfolio encompasses platinum thin film temperature detectors with linear response alongside multilayer metal oxide varistors. They deliver reliable thermal monitoring for power modules and surge protection handling peak pulses up to 6000A.

Platinum thin film SDT73 sensors conforming to international DIN IEC 751 curve standards
Linear PTC thermistors of LT73 family designed for precision circuit thermal compensation
Multilayer varistors NV73S capable of absorbing transient peak surge currents up to 6000A
Subminiature chip fuses TF series offering rapid and selective overcurrent protection

Engineering heritage of KOA Corporation and North American facility in Bradford

The engineering pedigree of Japanese group KOA Corporation originated in 1940 with the establishment of Koa Kogyo, dedicated to high reliability resistor manufacturing.

In 1980, the corporation acquired American manufacturer Speer Carbon in Bradford, Pennsylvania, establishing KOA Speer Electronics to serve industrial and electronics engineering sectors.

Today, KOA production and technical centers throughout Japan and the United States operate under IATF 16949 and ISO 9001 guidelines.

The enterprise ships billions of components each month under its Quality 1st mandate, ensuring dependable passive solutions for demanding automotive, industrial control, and instrumentation platforms.

Design and thermal characteristics of current sensing shunts series TLR, PS, UR

Low resistance metal alloy shunts of TLR and TLRH families are developed for current detection in switching power converters, motor drives, and battery management platforms.

Utilizing solid metal resistive elements forged from specialized alloys, these components deliver resistance down to 0.5 mOhm with ultra-low parasitic inductance below 1 nH.

Four-terminal Kelvin connection layouts in PSJ and PSI series eliminate solder joint resistance influence from analog measurement readings.

High dissipation configurations handle power ratings up to 10W while preserving linear temperature response across extreme operating spans from -65 up to +170 degrees Celsius.

Anti-sulfur protection of chip resistors RK73-RT and SG73-RT under harsh environments

Industrial plant atmospheres and automotive engine bays often contain sulfur compounds that corrode traditional silver inner electrodes to form non-conductive silver sulfide.

Resistors of RK73-RT and surge-resistant SG73-RT series feature special barrier alloy layers that prevent sulfur gas diffusion to inner terminations.

These components undergo extensive endurance validation in concentrated sulfur vapor at +105 degrees Celsius conforming to ASTM B809 standards with zero resistance shift.

This resilience ensures uninterrupted operation of industrial programmable controllers, valve actuators, and flow sensors in contaminated environments.

High voltage resistors HV73 and surge pulse elements series SG73 and RCR

For high voltage power supply circuits, inverter input stages, and medical diagnostic hardware, KOA Speer offers HV73 and automotive-grade HV73V surface mount resistors.

A serpentine thick film geometry eliminates localized electric field concentrations, reducing potential micro-arc breakdown hazards across high voltage differentials.

The components withstand working potentials up to 3000V alongside high surge pulses exceeding nominal ratings. Leaded RCR series units feature multi-layer flame retardant dielectric insulation, providing dependable electrical isolation and fire safety during severe inductive load switching events.

Precision thin film chip resistors RN73R for analog instrumentation circuits

Thin film resistors of RN73R series and high temperature RN73H variants are manufactured by vacuum sputtering nichrome film onto high purity alumina ceramic substrates. Advanced laser trimming achieves tight resistance tolerance down to ±0.05% with minimal current noise generation.

A low temperature coefficient of resistance of ±5 ppm/°C prevents thermal drift in instrumentation amplifiers, thermocouple interfaces, and high resolution analog-to-digital converters. An inorganic passivation barrier seals the resistive pattern against humidity and electrochemical degradation.

Platinum thermal sensors SDT73 and transient surge varistors NV73S

For continuous temperature monitoring of power semiconductors, motor windings, and battery packs, KOA Speer produces SDT73 platinum thin film sensors.

The platinum sensing layer deposited on an SMD substrate provides linear positive temperature response conforming to DIN IEC 751 industrial platinum thermometer standards.

To suppress high voltage transients and protect sensitive integrated circuitry, multilayer zinc oxide varistors of NV73S series feature sub-nanosecond response times and peak surge current absorption up to 6000A, protecting communication ports and power lines against electrostatic discharges.

KOA / KOA Speer Electronics and model names are trademarks of their respective owners and are used only to identify the equipment for which we source parts. SpareX is not an official dealer, distributor or representative of KOA / KOA Speer Electronics and is not affiliated with the trademark owner. Origin, documents and warranty are stated for each item in the quotation.