Rohm releases PFC and flyback control design
Rohm’s has announced a new reference design (REF67004) capable of controlling two commonly used power converter types in consumer and industrial power supply applications by using a single MCU.
The REF67004 boosts AC input using a critical conduction mode PFC converter, followed by a quasi-resonant flyback converter to deliver a regulated DC 24V output. It combines an analogue-controlled power stage circuit featuring Rohm’s silicon MOSFETs and gate driver ICs with a digitally managed power supply circuit built around the low-power LogiCoA MCU.
Features include a calibration function that compensates for variations in the external component characteristics, enabling the LogiCoA MCU to perform high-precision voltage configuration and overcurrent protection. This allows for reduced design margins, making it possible to select more compact (low power) power devices and inductors, ultimately helping to minimise PCB area and lower overall system costs.
The REF67004 also includes a logging function that allows the LogiCoA MCU to store operational data, such as input/output voltage, current, temperature, pre-shutdown system status, and cumulative operating time, in its built-in non-volatile memory. This data can be analysed to easily identify the root cause of power supply failures.
On top, various power control parameters and operational history can be easily configured and retrieved from a PC via UART (with a signal conversion device) using sample programs.
The design is part of Rohm’s LogiCoA power supply solution range: a hybrid approach that integrates the advantages of analogue and digital control.
