High Power High Reliability Ultra-Low Ohmic Chip Resistors Ideal for Current


PML100 ROHM has recently announced the development of the PML100 Series of wide electrode type chip resistors for current detection in a range of resistances, including high power models (i.e. 3W in the 6432 size) ideal for automotive applications.

The increasing integration of electronics in the automotive market has resulted in a greater demand for compact components featuring high reliability – in particular low ohmic chip resistors for current detection that can handle large currents. Unlike their smaller low-current counterparts, large current resistors (designed to handle current up to a few dozen amperes) are normally offered in relatively larger sizes, such as 6432. However, the larger mounting area involved increases the possibility of solder joint failures due to repeated expansion and contraction caused by thermal stress under severe operating environments (i.e. large temperature changes, high humidity).

ROHM prevents solder failures due to thermal stress by making the coefficient of expansion of the chip main body close to that of glass epoxy substrate. In addition, placing the electrodes on the wide side increases the junction area while reducing the distance between electrodes, minimizing the effects of thermal stress for stronger solder joint reliability.

A unique ‘trimless structure' is also utilized, resulting in 3W rated power with a resistance of only 0.5mΩ – optimal for applications such as power steering. The new units reduce mounting area by approximately 50% while maintaining characteristics.

Ultra-low Ohmic Wide Terminal Chip Resistors for Current Detection "PML100 Series" (PDF:839KB)

Key Features

  • Wide terminal format utilized for improved joint reliability and heat dissipation characteristics
  • Ultra-low resistance (from 0.5mΩ)
  • Even higher rated power than the PMR Series.
  • Completely lead-free.


Part No. Size(mm) Rated Power Resistance Range Resistance Tolerance Operating Temperature Range
PML100 6.4×3.2 3W(at 25ºC) 1.0、1.5、2.0、2.2mΩ J(±5%) -55 to 155ºC
PML100 6.4×3.2 2W 0.5mΩ J(±5%) -55 to 155ºC

Structural Comparison

Structural Comparison…Wide Terminal:Short Terminal