ROHM Develops Automotive Primary LDOs: Leveraging Original QuiCur Technology to Achieve Industry-Leading Load Response Characteristics

­ROHM Semiconductor announced the new BD9xxM5-C series of 45V rated, 500mA output primary LDO regulators (BD933M5EFJ-C, BD950M5EFJ-C, BD900M5EFJ-C, BD933M5WEFJ-C, BD950M5WEFJ-C, BD900M5WEFJ-C). These devices are suitable for supplying power to automotive electronic components such as Electronic Control Units (ECUs) that operate from vehicle batteries. 

In recent years, the number of onboard power supply system and functions has continued to grow as electrification in the automotive industry progresses. This increases the demand for primary LDOs that can directly step down the battery voltage to MCUs and other components used in ECUs. However, the energy supplied by the vehicle’s lead-acid battery is often subject to sudden voltage fluctuations, which primary LDOs are required to provide with excellent line-transient response in these conditions. 

At the same time, ECUs and other downstream devices often experience load current variations during operation that also demand excellent load-transient response characteristics. A high frequency response is essential for fast output voltage recovery, but it has been difficult to provide sufficient phase margin at the same time to ensure stable operation. In response, ROHM developed a novel solution that addresses these challenges. 

The BD9xxM5-C incorporates original QuiCur™ high-speed load response technology that delivers industry-leading load response characteristics to current fluctuations. For example, the LDO can maintain output to within 100mV of set voltage even as the load changes between 0 and 500mA in 1μs (rise time/fall time). Furthermore, low 9.5µA (typical) current consumption contributes to lower power consumption in automotive applications. These new products will be available in four packages, ranging from the compact HTSOP-J8 to the high heat dissipation TO252 (TO252-3/TO252-5) and HRP5 types. This allows users to select the most suitable package for each use case. 

Going forward, ROHM will continue to improve reliability while reducing power consumption in automotive applications by developing products utilizing its strengths in analog and other technologies.