PM8803TR Datasheet, PDF (1/34 Pages) STMicroelectronics – High-efficiency, IEEE 802.3at compliant integrated PoE-PD interface and PWM controller

PM8803
High-efficiency, IEEE 802.3at compliant integrated PoE-PD
interface and PWM controller
Datasheet − production data
Features
■ IEEE 802.3at compliant PD interface
■ Works with power supplied from Ethernet LAN
cables or from local auxiliary sources
■ Successful IEEE802.3at Layer1 classification
indicator
HTSSOP20
■ Integrated 100 V, 0. 45 Ω, 1 A hot-swap
MOSFET
■ Accurate 140 mA typ. inrush current level
■ Programmable classification current
■ Programmable DC current limit up to 1 A
■ Integrated high-voltage startup 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
Applications
■ VoIP phones, WLAN AP
■ WiMAX CPEs
■ Security cameras
■ PoE/PoE+ Powered Device appliances
Description
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 IEEE802.3at
Layer1 hardware classification, providing an
indication of Type 2 PSE successful detection to
the rest of the system.
The PM8803 has been designed to work with
power either from the Ethernet cable or from an
external power source such as a wall adapter,
ensuring prevalence of the auxiliary source with
respect to the PoE. The DC/DC section of the
PM8803 features a programmable oscillator
frequency, an adjustable slope compensation,
dual complementary low-side drivers,
programmable dead time and an internal
temperature sensor.
Table 1. Device summary
The PM8803 targets high-efficiency conversion at
all load conditions supporting flyback, forward,
forward with active clamp converters and
synchronous rectification.
Part number
Package
Packing
PM8803
PM8803TR
HTSSOP20
HTSSOP20
Tube
Tape and reel
November 2012
This is information on a product in full production.
Doc ID 018559 Rev 2
1/34
www.st.com
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