This reference design represents a PoE Class 8 converter designed for high efficiency conversion over a wide load range. It is based on the PM8805 PoE-PD interface and a DC-DC forward active clamp converter driven by the PM8804 PWM controller. The PM8805 system on package device embeds two active bridges and a Powered Device (PD) interface. It can be used in all medium-to-high power 2P and 4P high efficiency PoE and PoE+ applications such as point of sales and retail logistics devices.
The PM8804 PWM controller represents an integrated solution for a smart and efficient 48 V converter, including a programmable oscillator for the switching frequency, adjustable slope compensation, dual complementary low-side drivers with programmable dead time, programmable soft start, soft turn off and a programmable current sense blanking time.