MAX5972A Datasheet, PDF (1/13 Pages) Maxim Integrated Products – IEEE 802.3af/at-Compliant, Powered Device Interface Controller with Integrated Power MOSFET

19-4924; Rev 1; 2/10
EVAALVUAAILTAIOBNLEKIT
IEEE 802.3af/at-Compliant, Powered Device Interface
Controller with Integrated Power MOSFET
General Description
The MAX5972A provides a complete interface for a
powered device (PD) to comply with the IEEE® 802.3af/
at standard in a power-over-Ethernet (PoE) system. The
MAX5972A provides the PD with a detection signature,
classification signature, and an integrated isolation
power switch with inrush current control. During the
inrush period, the MAX5972A limits the current to less
than 180mA before switching to the higher current limit
(720mA to 880mA) when the isolation power MOSFET
is fully enhanced. The device features an input UVLO
with wide hysteresis and long deglitch time to compen-
sate for twisted-pair cable resistive drop and to assure
glitch-free transition during power-on/-off conditions. The
MAX5972A can withstand up to 100V at the input.
The MAX5972A supports a 2-event classification method
as specified in the IEEE 802.3at standard and provides a
signal to indicate when probed by Type 2 power-sourcing
equipment (PSE). The device detects the presence of
a wall adapter power-source connection and allows a
smooth switch over from the PoE power source to the
wall power adapter.
The MAX5972A also provides a power-good (PG) signal,
two-step current limit and foldback, overtemperature
protection, and di/dt limit.
The MAX5972A is available in a 16-pin, 5mm x 5mm,
TQFN power package. This device is rated over the
-40NC to +85NC extended temperature range.
Applications
IEEE 802.3af/at-Powered Devices
IP Phones, Wireless Access Nodes, IP Security
Cameras
WiMAXK Base Station
Features
S IEEE 802.3af/at Compliant
S 2-Event Classification or an External Wall Adapter
Indicator Output
S Simplified Wall Adapter Interface
S PoE Classification 0 to 5
S 100V Input Absolute Maximum Rating
S Inrush Current Limit of 180mA Maximum
S Current Limit During Normal Operation Between
720mA and 880mA
S Current Limit and Foldback
S Legacy UVLO at 36V
S Overtemperature Protection
S Thermally Enhanced, 5mm x 5mm, 16-Pin TQFN
Ordering Information
PART
TEMP RANGE
PIN-
PACKAGE
SLEEP
MODE
MAX5972AETE+ -40NC to +85NC 16 TQFN-EP* ––
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Pin Configuration
TOP VIEW
N.C. 1
VDD 2
DET 3
I.C. 4
16 15 14 13
+
MAX5972A
EP*
12 CLS
11 2EC
10 PG
9 WAD
WiMAX is a trademark of WiMAX Forum.
IEEE is a registered service mark of the Institute of Electrical
and Electronics Engineers, Inc.
5
6
7
8
TQFN
(5mm × 5mm)
*EP = EXPOSED PAD. CONNECT TO VSS.
________________________________________________________________ Maxim Integrated Products   1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.