Stackpole Electronics has introduced the RMAN series of thick film chip resistors built on aluminum nitride (AlN) substrates, targeting designs that are power‑limited by heat rather than footprint.
The use of AlN significantly improves thermal conductivity compared to conventional alumina, enabling higher power density in familiar 1206 and 2512 sizes for power electronics, industrial and other thermally demanding applications.
Key features and benefits
The RMAN series is a thick film high power chip resistor family using aluminum nitride substrate technology instead of standard alumina. This substrate change is aimed at overcoming the thermal bottleneck that typically limits power ratings in conventional thick film chip resistors.
The central technical differentiator of the RMAN series is the use of aluminum nitride substrate instead of alumina. Aluminum nitride offers much higher thermal conductivity, which improves heat spreading from the resistive element to the terminations and into the PCB or heatsinking structure.
Key features include:
- Aluminum nitride (AlN) substrate for significantly higher thermal conductivity compared to alumina
- Thick film resistive technology for a well‑known, stable and cost‑effective construction
- High power density in standard chip sizes:
- 2.4 W in 1206 package size
- 3.4 W in 2512 package size
- Power ratings specified while maintaining hot‑spot and terminal temperatures within safe operating limits
- Backward‑compatible form factors that fit standard 1206 and 2512 land patterns (check exact pad geometry in the manufacturer datasheet)
Practical benefits for design engineers:
- Improved power handling in the same board area, allowing downsizing from larger resistor packages or parallel arrays
- Better thermal performance margin in hot ambient conditions or constrained airflow environments
- Potential reduction in resistor count in power paths, simplifying layouts and BoM
- Use of familiar thick film technology, easing qualification compared to more exotic solutions
Typical applications
The RMAN series is suitable wherever surface‑mount resistors are operating near their thermal limits and conventional alumina‑based chips are constraining power density. Typical use cases include:
- Power electronics:
- Current‑sense and damping resistors in PFC stages
- Snubber, bleeder or preload resistors in AC‑DC and DC‑DC converters
- Gate drive and shaping resistors near power switches where local heating is high
- Industrial and automation:
- Motor drives and inverters, braking and damping networks
- Power supplies for control cabinets with limited airflow
- Energy and infrastructure:
- Chargers and rectifiers
- Auxiliary power modules in UPS and energy storage systems
- Other high‑power SMD resistor applications where footprint and temperature rise are critical design constraints
Because the series is based on thick film technology, it can serve in many of the same roles as conventional high‑power chip resistors, but with an emphasis on applications where the thermal path to the PCB and ambient is a limiting factor.
Source
This article is based on an official press release by Stackpole Electronics announcing the RMAN thick film high power aluminum nitride substrate chip resistor series.