Overview: PD70224
IdealBridge™ Dual MOSFET-Based Bridge Rectifier
Introduction
PD70224 is a dual pack of MOSFET-based full-bridge rectifiers. It contains low-RDS 0.16 Ω N-channel MOSFETs for much higher overall efficiency and higher output power, particularly when used in Powered Devices for Power over Ethernet (PoE) applications. The entire drive circuitry for driving the MOSFETs is on-chip, including a charge pump for driving the high-side N-channel MOSFETs. The total forward drop (bridge offset) introduced by the IdealBridge™ rectifier is only 192 mV at 0.6 A, compared to a standard bridge rectifier that typically presents 2000 mV of forward drop. PD70224 IdealBridge™ can support over 2 A current, making it the ideal choice for IEEE®802.3bt (Type 3 and Type 4), IEEE 802.3at and IEEE 802.3af (Type 1 and Type 2). The PD70224 also supports legacy 4 pair standards such as UPoE (60 W) and POH (Power over HDBase-T, 95 W).. In addition, PD70224 is capable of helping to identify at the physical layer itself whether a 2-pair PSE or a 4-pair PSE is providing power over the cable. It does that by sensing the voltage on the line (un-rectified) side of the pairs.
