30W PoE PD and DC-DC Controller AS1138 FEATURES GENERAL DESCRIPTION The AS1138 is a single-chip, highly integrated CMOS Full support of both IEEE Std. 802.3af-2005 and IEEE solution for Power over Ethernet (PoE) Powered Devices Std. 802.3at-2009 power requirements requiring input power of up to 30Watts. Applications include 2-Event classification for 802.3at higher power PDs Voice over IP (VoIP) Phones, Wireless LAN Access Point, Robust Type 2 PSE detector with proprietary digital Security Cameras, WiMAX Terminals, Point-of-Sales filtering for line noise to eliminate false positives Terminals, RFID Readers, Thin Clients and Notebook computers. IEC 61000-4-2/3/4/5/6 requirements for EMC Compliance The AS1138 integrates input surge protection, a PD controller and a low-emission DC-DC controller. The Integrated Surge Protection for 15kV/8kV System level AS1138 implements all of the physical layer Powered ESD Compliance Device (PD) functionality, as required by IEEE 802.3af- Integrated DC-DC controller for exceptional EMI 2005 and IEEE 802.3at-2009 standards. This includes 2- performance event classification, Type 2 PSE detection indicator (ATDET), PD detection, under-voltage lock out (UVLO), Programmable DC current limit up to 720mA for 30W and Hot-Swap FET integration. applications The AS1138 has been architected to address both EM Seamless support for local power, down to 9.5V emission concerns and surge/over-voltage protection in Implemented in robust 100V automotive process PoE applications. The chip implements many design Low Rds-on Hot-Swap FET (typical 0.8) features that minimize transmission of system common- mode noise onto the Unshielded Twisted Pair (UTP). On- Integrated Short-Circuit Protection chip integration of surge protection provides faster Over temperature protection response to surge events and limits stray surge current from Industrial temperature range, -40C to +85C passing through sensitive circuits, such as the Ethernet PHY. The device is designed to provide safe, low- 5x5 mm, 20 lead QFN Package, RoHS compliant impedance discharge paths directly to the earth ground, resulting in superior reliability and circuit protection. TYPICAL APPLICATIONS Pan, tilt and zoom (PTZ), security and web cameras Voice over IP (VoIP) phones Wireless LAN access points, WiMAX terminals Point-of-sale (PoS) terminals, RFID terminals Thin clients and notebook computers Fiber-to-the-home (FTTH) terminals SIMPLIFIED APPLICATION DIAGRAM 10/100/1K GMII Processor PHY Local Power AS1138 Surge Protection LVMODE Local Adapter Control Current Signature Limit / DC-DC Extended Sense Controller Classification With UVLO Managed Thermal Emissions Limit Control AT ATDET Protection Detection PD Controller Kinetic Technologies July 2018 Revision 03h www.kinet-ic.com 1 RJ45AS1138 TABLE OF CONTENTS FEATURES .................................................................................................................................................................................. 1 GENERAL DESCRIPTION ........................................................................................................................................................... 1 TYPICAL APPLICATIONS ........................................................................................................................................................... 1 SIMPLIFIED APPLICATION DIAGRAM ....................................................................................................................................... 1 TABLE OF CONTENTS ............................................................................................................................................................... 2 FIGURES ..................................................................................................................................................................................... 3 TABLES ....................................................................................................................................................................................... 3 PIN ASSIGNMENTS AND DESCRIPTIONS ................................................................................................................................ 4 TYPICAL PERFORMANCE CHARACTERISTICS ....................................................................................................................... 8 FUNCTIONAL DESCRIPTION ................................................................................................................................................... 15 Overview of PoE .................................................................................................................................................................... 15 AS1138 PoE Design............................................................................................................................................................... 15 POWER FEED ALTERNATIVES FOR 10/100/1000 ETHERNET SYSTEMS ............................................................................ 16 AS1138 OVERVIEW .................................................................................................................................................................. 17 Rectification and Protection .................................................................................................................................................... 18 PD Controller .......................................................................................................................................................................... 18 Modes of Operation ................................................................................................................................................................ 18 Reset ...................................................................................................................................................................................... 18 Detection Mode ...................................................................................................................................................................... 18 Classification Mode ................................................................................................................................................................ 18 Idle Mode ............................................................................................................................................................................... 19 On State ................................................................................................................................................................................. 19 Local Power Mode (LVMODE) ............................................................................................................................................... 19 PD CONTROLLER POWER AND THERMAL PROTECTION ................................................................................................... 20 Under Voltage Lock Out (UVLO) ............................................................................................................................................ 20 Inrush Current Limit / Current Sense ...................................................................................................................................... 20 Thermal Limit / Protection ...................................................................................................................................................... 20 POE POWER-ON STARTUP WAVEFORM ............................................................................................................................... 21 ATDET PIN ................................................................................................................................................................................ 21 DC-DC CONTROLLER .............................................................................................................................................................. 22 Overview ................................................................................................................................................................................ 22 Programmable PWM Frequency ............................................................................................................................................ 22 Current-Limit/Current Sense .................................................................................................................................................. 22 Low Load Current Operation .................................................................................................................................................. 22 Compensation and Feedback ................................................................................................................................................ 23 Soft-Start ................................................................................................................................................................................ 23 DC-DC CONVERTER TOPOLOGIES ........................................................................................................................................ 23 Isolated Topologies ................................................................................................................................................................ 23 Non-Isolated Topologies ........................................................................................................................................................ 23 APPLICATION CIRCUITS .......................................................................................................................................................... 24 THERMAL DE-RATING AND BOARD LAYOUT CONSIDERATIONS ....................................................................................... 25 PHYSICAL DIMENSIONS .......................................................................................................................................................... 26 IMPORTANT NOTICES ............................................................................................................................................................. 27 Legal notice ............................................................................................................................................................................ 27 Reference design policy ......................................................................................................................................................... 27 Life support policy .................................................................................................................................................................. 27 SUBSTANCE COMPLIANCE ................................................................................................................................................. 27 Kinetic Technologies July 2018 Revision 03h www.kinet-ic.com 2