PM8803: Integrated PoE+ PD interface and PWM controller STMicroelectronics The solution for high-efficiency PoE+ powered devices The PM8803 combines a standard IEEE 802.3at interface, a current-mode PWM controller and a best-in-class hot-swap MOSFET in a single package. Designed in a 100 V capable technology, the PM8803 supports forward active clamp as well as synchronous flyback topologies for high efficiency under any load condition. Key features QQ QQ QQ QQ In addition, the PM8803 indicates successful connection with a PSE implementing 2-event classification. QQ Housed in an HTSSOP20 package for better thermal performance, the PM8803 allows simple and robust design of PDs that may also be powered from auxiliary sources. QQ The PM8803 extends ST’s PoE/ PoE+ portfolio. QQ QQ QQ QQ QQ QQ QQ IEEE 802.3at compliant powered device interface Works with power supplied from Ethernet LAN cables or from local auxiliary sources Integrated 100 V, 0.45 Ω, 1 A hot-swap MOSFET Successful IEEE 802.3at layer1 classification indicator Accurate 140 mA typ. inrush current level Programmable DC current limit up to 1 A High-voltage start-up bias regulator Thermal shutdown protection Current-mode pulse width modulator Programmable oscillator frequency 80% maximum duty cycle with internal slope compensation Support for flyback, forward, forward active clamp, flyback with synchronous rectification Supports both isolated and non-isolated applications Main applications QQ QQ QQ QQ QQ QQ QQ QQ VoIP phones VideoIP phones WLAN access points Security cameras WiMax CPEs RFID readers Pico/femto cells PoE/ PoE+ powered device appliances www.st.com/poe The PM8803 integrates a standard-compliant power over Ethernet (PoE) interface and a current-mode PWM controller to simplify the design of the power supply sections of all powered devices. The PoE/PoE+ interface incorporates all the functions required by the IEEE 802.3at including detection, classification, undervoltage lockout (UVLO) and in-rush current limitation. The PM8803 specifically performs IEEE 802.3at layer1 hardware classification scheme providing an indication of Type 2 PSE successful detection to the rest of the system. The integrated switching regulator of the PM8803 has been designed to work with power either form the Ethernet cable connection or from an external power source such as an AC adapter. The DC-DC section of the PM8803 features a programmable oscillator frequency, adjustable slope compensation, dual complementary low-side drivers, programmable dead time and internal temperature sensor. The PM8803 targets high-efficiency conversion under all load conditions supporting flyback, forward, forward active clamp and synchronous rectification. VOUT VOUT PSE 24.9 kOhm T2P VB VC GAT1 SA DC/DC VB SP Hot-swap CTL controller CS DCC GAT2 CLS RTN1 ARTN RTN2 VSS VDD IEEE 802.3at DET interface FRS DT PoE+ section with PM8803 in forward AC topology PoE selection table Part number PM8800A PM8803 Supported standard IEEE 802.3at, Type 1 IEEE 802.3at, Type 1-2 Signature resistor Integrated DC-DC regulator RDS(on) internal HS MOSFET Type 2 PSE indicator Inrush current Max DC current Support for forward AC Auxiliary source range Yes Yes 0.5 No Programmable 800 mA No 12 to 57 V No Yes 0.45 Yes 140 mA 1000 mA Yes 12 to 57 V © STMicroelectronics - October 2010 - Printed in Italy - All rights reserved The STMicroelectronics corporate logo is a registered trademark of the STMicroelectronics group of companies All other names are the property of their respective owners Order code: FLPM88031010 For more information on ST products and solutions, visit www.st.com