ROHM High Surge 0402 Chip Resistors

ROHM has developed the SDR01 series of chip resistors designed to provide high surge resistance and a rated power of 0.33 W within a compact 0402 footprint. The surface-mount components are engineered to consolidate printed circuit board space in power supply and interface circuits across automotive, industrial, consumer electronics, and artificial intelligence server applications.

Engineering Challenges in Dense Electronic Mounting
As electronic equipment becomes increasingly sophisticated and requires higher power transmission, the demand for compact electronic components with high power handling capabilities rises in the automotive, industrial, and consumer markets. Modern power supply circuits and peripheral interfaces require robust resistance to electrical surges and electrostatic discharge. Traditionally, protecting against these transient voltages required larger resistor packages or multiple components connected in parallel, which consumes valuable board space and complicates the thermal design of high-density mounting areas.

Resistive Element Optimization and Thermal Performance
To address the requirements of miniaturized high-power architectures, ROHM optimized the resistive element and electrode designs of the SDR01 series. This internal structural configuration enables the resistors to guarantee a rated power of 0.33 W in the 0402 size, which corresponds to the 1005 metric dimensions. According to a ROHM study dated September 10, 2026, this represents a class-leading power rating for this specific footprint. The components maintain their full 0.33 W power rating up to a rated terminal temperature of 125 degrees Celsius. This elevated thermal threshold facilitates their integration into demanding thermal environments, such as zones directly adjacent to heat-generating components, thereby reducing the thermal management burden on the overall system design.

Temperature Coefficient and Circuit Stability
In addition to surge mitigation and power handling, the SDR01 series achieves a temperature coefficient of resistance of plus or minus 100 parts per million per degree Celsius across a resistance range of 10 ohms to 2.2 megaohms. By suppressing fluctuations in the resistance value caused by ambient temperature changes, the components ensure stable circuit operation. This stability contributes directly to the reliability and miniaturization of power supplies and peripheral interface networks. The products have entered mass production and are available for purchase through the ROHM online store as well as online distributors such as DigiKey and Farnell.

Additional Context
This section details technical specifications and competitive benchmarking not included in the original product announcement

Within the market for compact surge surface-mount resistors, the ROHM SDR01 series establishes a new power density benchmark for the 0402 metric size. Comparable surge chip resistors in the 0402 footprint, such as the Panasonic ERJ-PA2 series and the Yageo SR0402 series, typically offer maximum power ratings of 0.20 W and 0.125 W, respectively. By achieving a 0.33 W rating in the same physical dimensions, the ROHM architecture allows hardware engineers to replace larger 0603 or 0805 metric components with the smaller 0402 package. This capability directly reduces the component footprint and addresses the spatial constraints of dense artificial intelligence server boards and automotive electronic control units.

Edited by Maria Brueva, Induportals editor - adapted by AI.

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