Rohm’s Latest LDO Regulator ICs Target Nanoscale Output Capacitance

June 20, 2022 by Abdulwaliy Oyekunle

Tackling capacitor challenges, Rohm's latest low-dropout (LDO) regulators aim to offer stability in power supply circuits designed with low capacitance values.

When designing power supplies, designers often employ power supply ICs to achieve efficient power conversion while maintaining a low current consumption. Thus, manufacturers work round the clock to fabricate power supply ICs to meet the design specifications required in the industry.

As an active component in an electric circuit, capacitors are one of the many components analog circuit designers employ in fabricating power supply circuits. Overall, a dielectric material separates the conducting plates of a capacitor, and the component can store enough charge in the electric field between its plates to keep a circuit working. 

What’s more, capacitors are utilized to stabilize power supply circuits and voltage sources that are needed in a wide range of electrical applications.


An example of power supply design technology is Rohm’s Nano Cap Technology, which claims to integrate the combination of advanced circuit design, improved layout, and process together.

An example of power supply design technology is Rohm’s Nano Cap Technology, which claims to integrate the combination of advanced circuit design, improved layout, and process together. Image used courtesy of Rohm


Hoping to push forward innovation in power supply IC design, Rohm strives to help analog design engineers fabricate power supply ICs to solve capacitance issues in power supply circuits. With its latest Nano Cap technology, Rohm targets applications in the automotive industry to provide stability in power supply circuits.

In this article, we'll look at Rohm's Nano Cap technology, how the new solution might solve capacitance issues in power supply circuits, and its latest LDO regulator releases


Nano Cap Technology Solves Capacitances Issues

To begin with, one challenge facing capacitance is that state-of-the-art technology innovations and development in electric vehicles require designers to employ bulky PCB layouts and external active components like capacitors. However, this could increase cost and consume time spent during the development cycle.

At the same time, there has been a demand to reduce the number of active components like capacitors used to design modern electronic devices, especially power supply devices. Thus, designers resorted to using small-sized capacitors in power supply circuits. However, a stable operation is hard to achieve when a 1 μF capacitor is connected to the output of a linear regulator.

To address this problem, analog designers at Rohm have introduced an ultra-stable control technology called the Nano Cap technology that claims to eliminate stability problems in power supply circuits.


A comparison between conventional capacitor configurations (left) and a Nano Cap configuration (right). Image used courtesy of Rohm


This technology aims to incorporate a combination of advanced circuit design and improved processes and layout to achieve an optimized control system that provides stability in power supply and analog circuits that are useful in a wide range of applications, including automotive, industrial systems, and so on.

The technology offers power supply ICs voltage fluctuations of ±3.6% for stable operations at 100 nF. Thus, the LDO linear regulators equipped with the technology can meet the industry requirement of ±5.0% max voltage fluctuations at 100 nF.

According to Rohm, the Nano Cap technology minimizes parasitic factors associated with wiring and amplifiers. This attribute produces a linear regulator with a reduced output capacitance that is less than 1/10th of conventional solutions. In addition, the technology enables the miniaturization of components and PCB layouts used in analog circuit designs.


Rohm’s New Series of LDO Regulators

Recently, Rohm introduced a family of LDO regulators equipped with the Nano Cap technology: the BD9xxN1-C series

The products in this series include: 

These LDO linear regulators are targeted toward automotive applications and give excellent response performance with output nanoscale capacitors with a capacitance value of 100 nF.

According to the datasheet, the BD9xxN1-C family of linear regulators is said to consume current as low as 28 μA and could comfortably operate a wide range of input voltages from 3 V to 42 V. 

According to the manufacturers, unique features in the regulators include over-current protection (OCP), thermal shutdown protection (TSD), and under-voltage lockout (UVLO). The regulators are AEC-Q100 certified and are packaged in an SSOP5 package.


Block diagram of the BD9xxN1-C family of LDO regulators.

Block diagram of the BD9xxN1-C family of LDO regulators. Image used courtesy of Rohm


Rohm looks forward to expanding the LDO regulator series by adding 22 more products towards the end of 2022 and 24 products by 2023. It is said that the products would cover a wider range of applications.