Industry's first analog-digital fusion control power supply solution

ROHM has launched LogiCoA, a power supply solution for small to medium-power industrial and consumer equipment (30W to 1kW class). It delivers the same functionality as fully digital control power supplies at low power consumption and cost equivalent to analog power types.

Analog-controlled power supplies are commonly used in industrial robotics and semiconductor manufacturing equipment that function in the medium power range. However, in recent years, these power supplies also need to provide a high level of reliability and precise control that makes it difficult to fulfil market demands with analog-only configurations. On the other hand, while fully digitally controlled power supplies allow fine control and settings, they are not widely adopted in the small to medium power range due to the high power consumption and cost of the digital controller. To address this issue, the company developed the LogiCoA power solution that uses the strengths of analog and digital technologies. High-performance, low-power LogiCoA MCUs are used to facilitate control of various power supply topologies.

The LogiCoA brand represents a design philosophy of fusing digital elements to maximise the performance of analog circuits. This power solution claims to be the industry's first 'analog-digital fusion control' power supply that combines a digital control block centred around the device's MCU with analog circuitry comprised of silicon MOSFETs and other power devices.

In a fully digital control power supply, the functions handled by digital controllers such as high-speed CPUs or DSPs can be processed by low-bit MCUs, making it possible to attain increased functionality that is difficult to realise with an analog control power supply at low power consumption and cost. This solution permits the correction of performance variations in peripheral components according to the power supply circuit by storing varied settings, such as current and voltage values in the MCU. As a result, there is no requirement to consider design margins, unlike analog control power supplies, which contribute to smaller power supplies that deliver greater reliability. On top of that, as operation log data can be recorded in the MCU's nonvolatile memory, it is excellent for power supplies in industrial equipment that require logging as a backup in case of malfunction.

The evaluation reference design REF66009 enables users to experience the LogiCoA power supply solution in a non-isolated buck converter circuit. Various tools required for evaluation are also offered, including circuit diagrams, PCB layouts, parts lists, sample software, and support documents, while actual device evaluation is possible by utilising the optional LogiCoA001-EVK-001 evaluation board.