Features

• Fully supports both IEEE® Std. 802.3af-2005

and IEEE® Std. 802.3at-2009

• “2-Event” classification for 802.3at higher

power PDs

• Robust Type 2 PSE detector with proprietary

digital filtering line noise eliminating false

positives

• IEC 61000-4-2/3/4/5/6 requirements for EMC

Compliance

• Integrated Surge Protection for 15kV/8kV

System level ESD Compliance

• Exceptional EMI performance

• Programmable DC current limit up to 730mA

for 30W applications

• Seamless support for local power, down to

9.5V

• Low Rds-on Hot-Swap FET (typical 0.6Ω)

• Integrated Short-Circuit Protection

• Over temperature protection

• 5x5 mm, 20 lead QFN Package

• Industrial temperature range (-40°C to +85°C)

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

Brief Description

The KTA1137A is a single-chip, highly integrated CMOS

solution for Power over Ethernet (PoE) Powered Devices

requiring input power of up to 30Watts. Applications

include Voice over IP (VoIP) Phones, Wireless LAN

Access Point, Security Cameras, WiMAX Terminals, Pointof-

Sales Terminals, RFID Readers, Thin Clients and

Notebook computers.

The KTA1137A integrates input surge protection, a PD

controller and a low-emission DC-DC controller. The

KTA1137A implements all of the physical layer Powered

Device (PD) functionality, as required by IEEE® 802.3af-

2005 and IEEE® 802.3at-2009 standards. This includes 2-

event classification, Type 2 PSE detection indicator

(ATDET), PD detection, under-voltage lockout (UVLO),

and Hot-Swap FET integration.

The KTA1137A has been architected to address both EM

emission concerns and surge/over-voltage protection in

PoE applications. The chip implements many design

features that minimize transmission of system commonmode

noise onto the Unshielded Twisted Pair (UTP). Onchip

integration of surge protection provides faster

response to surge events and limits stray surge current

from passing through sensitive circuits, such as the

Ethernet PHY. The device is designed to provide safe, lowimpedance

discharge paths directly to the earth ground,

resulting in superior reliability and circuit protection.