MAX5982A Datasheet, PDF (1/17 Pages) Maxim Integrated Products – IEEE 802.3af/at-Compliant, Powered Device Interface

19-5960; Rev 0; 6/11
IEEE 802.3af/at-Compliant, Powered Device Interface
Controllers with Integrated 70W High-Power MOSFET
General Description
The MAX5982A/MAX5982B/MAX5982C provide a com-
plete interface for a powered device (PD) to comply with
the IEEE^® 802.3af/at standard in a power-over-Ethernet
(PoE) system. The MAX5982A/MAX5982B/MAX5982C
provide the PD with a detection signature, classifica-
tion signature, and an integrated isolation power switch
with inrush current control. During the inrush period,
the MAX5982A/MAX5982B/MAX5982C limit the current
to less than 182mA before switching to the higher cur-
rent limit (1700mA to 2100mA) when the isolation power
MOSFET is fully enhanced. The devices feature an input
UVLO with wide hysteresis and long deglitch time to
compensate for twisted-pair cable resistive drop and to
assure glitch-free transition during power-on/-off condi-
tions. The MAX5982A/MAX5982B/MAX5982C can with-
stand up to 100V at the input.
The MAX5982A/MAX5982B/MAX5982C support a
2-Event classification method as specified in the IEEE
802.3at standard and provide a signal to indicate when
probed by a Type 2 power sourcing equipment (PSE).
The devices detect the presence of a wall adapter power
source connection and allow a smooth switchover from
the PoE power source to the wall power adapter.
The MAX5982A/MAX5982B/MAX5982C also provide a
power-good (PG) signal, two-step current limit and fold-
back, overtemperature protection, and di/dt limit. A sleep
mode feature in the MAX5982A/MAX5982B provides low
power consumption while supporting Maintain Power
Signature (MPS). An ultra-low-power sleep mode feature
in the MAX5982A/MAX5982B further reduces power
consumption while still supporting MPS. The MAX5982A/
MAX5982B also feature an LED driver that is automati-
cally activated during sleep mode.
The MAX5982A/MAX5982B/MAX5982C are available in
a 16-pin, 5mm x 5mm, TQFN power package. These
devices are rated over the -40NC to +85NC extended
temperature range.
Features
S Sleep Mode and Ultra-Low-Power Sleep
(MAX5982A/MAX5982B)
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 0–5
S 100V Input Absolute Maximum Rating
S Inrush Current Limit of 182mA Maximum
S Current Limit During Normal Operation Between
1700mA and 2100mA
S Current Limit and Foldback
S Legacy UVLO at 36V
S LED Driver with Programmable LED Current
(MAX5982A/MAX5982B)
S Overtemperature Protection
S Thermally Enhanced, 5mm x 5mm, 16-Pin TQFN
Applications
IEEE 802.3af/at Powered Devices
IP Phones, Wireless Access Nodes, IP Security
Cameras
WiMAXK Base Stations
Ordering Information appears at end of data sheet.
WiMAX is a trademark of WiMAX Forum.
IEEE is a registered service mark of the Institute of Electrical
and Electronics Engineers, Inc.
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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.