Alloy Resistors: The “Precision Eye” for Current Sensing in BMS and AI Servers
In electronic systems, current sensing is the foundation for achieving precise control and safety protection. Alloy resistors (also known as precision current-sensing resistors) are exactly the key components that perform this core function. Based on Ohm’s law U = I × R, they convert large currents into precisely measurable small voltage signals, providing real-time current data to the system, and are known as the “precision eye” of circuits.
In the new energy BMS field, alloy resistors serve as the “current sensor” of the battery management system. The BMS is responsible for real-time collection of charge and discharge currents, calculation of remaining state of charge (SOC), and triggering overcurrent and short-circuit protection—the underlying data for all these functions comes from the sensing resistor connected in series in the main circuit. With characteristics of low resistance, low temperature drift, and high power, alloy resistors can maintain accurate sensing under high-current conditions ranging from tens to hundreds of amperes, ensuring safe battery operation and accurate range estimation. Compared with ordinary thick-film resistors, alloy resistors use a solid metal alloy for conduction, offering lower temperature drift, higher precision, and stronger pulse resistance, making them better suited to high-reliability application scenarios such as new energy vehicles and energy storage power stations.
In the AI server field, as CPU/GPU power consumption continues to rise, power supply modules are imposing increasingly stringent requirements on current sensing accuracy. VRM power supply circuits need to precisely monitor the current of each phase to achieve dynamic load regulation and overcurrent protection. With the advantages of low TCR and high stability, alloy resistors can provide reliable sensing data in high-current, high-density environments, ensuring stable server operation.
The CRHD/CRHX series stamped and plastic-encapsulated alloy resistors from Zhongxin Inductance (CP) adopt self-developed automated production processes and feature high precision, low temperature drift, and high reliability. With monthly capacity reaching 100KKPCS, they can meet the current sensing needs of customers in multiple fields such as new energy, industrial control, and communication equipment.