New Industry Products

Digital Power-Factor Controller Leverages Analog Performance and Stability

August 14, 2019 by Paul Shepard

Combining the flexibility of digital power with the responsiveness of analog algorithms, STMicroelectronics' STNRGPF12 dual-channel interleaved boost-PFC controller is easily configured and optimized using the Company's eDesignSuite software.

Suited to applications over 600W, the STNRGPF12 enhances efficiency and reliability in equipment as diverse as industrial motor controls, charging stations, uninterruptable power supplies, 4G and 5G base stations, welding machines, telecom switches, home appliances, and data-center power supplies.

The STNRGPF12 operates in continuous-conduction mode (CCM) at fixed frequency with average-current-mode control. The best of both digital and analog worlds meets in the STNRGPF12's inner and outer control loops. The inner current loop utilizes a hardware analog Proportional-Integral (PI) compensator, while the outer voltage loop is performed by a digital PI controller with fast dynamic response. This enables the STNRGPF12 to manage cascaded control of the voltage and current loops to regulate the output voltage by acting on the total average inductor current.

Rich feature integration includes digital inrush-current limiting, which leverages silicon controlled rectifiers (SCR) in the high-side switching circuitry to facilitate soft-start management and enhance system robustness.

The STNRGPF12 also supports load feed-forward, current balancing, phase shedding, and fan control. An integrated UART allows access to non-volatile memory for user configuration of PFC parameters to meet specific application needs and permits monitoring of parameters in the field.

Users can unleash the maximum potential of the STNRGPF12 by taking advantage of ST's extensive ecosystem, which includes the STEVAL-IPFC12V1 dual-channel 2kW interleaved PFC reference design, as well as the configuration software, to jump-start their designs.

The STNRGPF12 is in production now in TSSOP38 package, from $2.40 for orders of 1000 pieces.