IXYS announced the IXRD1004 – High Power Two-Phase Digital Power Factor Correction (PFC) reference design. It is based on Zilog’s 8-bit Z8F6481 microcontroller, a member of the Z8 Encore! XP F6482 series of microcontrollers, and IXYS power transistors and rectifiers.
The PFC uses a two-phase, interleaved boost-type conversion architecture, and a high power factor is achieved by adjusting the peak current value with respect to the rectified input voltage. The inrush current at the start-up is digitally controlled and the bulk capacitor is pre-charged using a switching MOSFET. It incorporates the digital inrush current concepts demonstrated in another IXYS reference design, the IXRD1002 High Power Digital Inrush Current Controller.
The input voltage of the PFC ranges from 105VAC to 140VAC while the output voltage is at 400V. The maximum output power is 1.06kW with the load current at 2.65A. The 3 switches needed in this design are realized using IXYS’ latest 650 Ultra Junction Power MOSFETs, the IXTH34N65X2 and IXTH80N65X2.
This reference design consists of a microcontroller module and main power board. Designed as an add-on device, the MCU module includes two 8-bit MCUs that generate the gate control signals to maintain current balance between the two interleaved conversion phases. It also enables a high efficiency in a wide range of loads, keeps the output voltage stable, and provides overload and overvoltage protection functions.