SMPS controller simplifies access to digital power

Article By : EE Times Asia

The STNRGPF01 supports three interleaved phases, ensuring low ripple currents and simplifying EMI-filter design.

STMicroelectronics has introduced the STNRGPF01 switched-mode power supply (SMPS) controller, which delivers the flexibility and high efficiency of digital power without the technical challenges and time to develop custom digital signal processor (DSP) code.

In high-power applications above 1 or 2kW, interleaved CCM PFC (Continuous-Current Mode, Power-Factor Correction) topologies are mandatory to handle the said power levels with reasonable magnetic volume and current split. Moreover, the quest for higher efficiency, connectivity and configuration options encourages the use of expensive and complex DSP solutions.

ST’s new SMPS controller for interleaved boost-PFC topologies is configured using ST’s eDesignSuite online design environment, and has I2C and UART interfaces for monitoring and control. It supports three interleaved phases, which ensures low ripple currents, simplifies EMI-filter design using small inductors and permits a wide power range from 500W to over 20kW. Moreover, the STNRGPF01’s flexible, configurable phase-shedding strategy optimises the number of active phases automatically to maintain high efficiency across all load conditions, according to the company.

The STNRGPF01 operates in CCM at fixed frequency with average-current-mode control. A hardware inner-current loop ensures accurate cycle-by-cycle regulation, while a digital proportional-integral (PI) controller manages the outer voltage loop to ensure fast dynamic response. The frequency can be programmed from a few kHz to over 300kHz, to control either an IGBT or MOSFET output stage. Other configurable features include inrush-current limiting and PFC soft power-on.

By delivering the advantages of digital power through easy configuration in eDesignSuite, the STNRGPF01 enables superior flexibility, reliability, safety and energy efficiency in equipment such as industrial welders, motor drives, pumps, uninterruptible power supplies (UPS), industrial or consumer air conditioners and domestic appliances such as refrigerators, washers, dryers and cookers.

The STNRGPF01 is in full production, packaged as a TSSOP38, priced from $3.50 for orders of 1,000 pieces.