PD70224 IdealBridge™ Dual MOSFET Bridge Rectifier

     Microchip Technology's PD70224 is a dual MOSFET based full bridge rectifier. It contains low RDS 0.16 Ω N-channel MOSFETs for higher overall efficiency and higher output power, especially when used for powered devices (PDs) in Power over Ethernet (PoE) applications. The entire driver circuit for driving the MOSFET is on-chip, including the charge pump for driving the high-side N-channel MOSFET. The total forward voltage drop (bridge offset) introduced by the IdealBridge rectifier is only 192 mV at 0.6 A, while standard bridge rectifiers typically exhibit a forward voltage drop of 2000 mV.

     The PD70224 IdealBridge can support more than 1 A, making it ideal for modern energy-efficient 2-pair applications compliant with IEEE 802.3af and IEEE 802.3at (Type 1 and 2), as well as 4-pair PDs such as IEEE 802.3bt and HDBase-T ( Ideal for PoH) power supply. Additionally, the PD70224 can help identify at the physical layer itself whether a 2-pair or 4-pair PSE is being powered over the cable. It does this by sensing the pair voltage on the line (unrectified) side.

     Active circuit with low forward voltage drop to replace dissipative passive diode bridge characteristics, separate driver circuit for MOSFET and power presence indicator signal for identifying 4 pairs of bridged power supplies, designed to support IEEE 802.3af/ at/bt and PoH and integrated 0.16 Ω N-channel MOSFET for a total path resistance of 0.3 Ω，Low leakage, <10 µA during detection and wide operating voltage range, up to 57 V, -40 °C to +85 °C, 40-pin, 6 mm x 8 mm QFN package, MSL3, and RoHS compliant