_______________________________________________________________ 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.
MAX5984
Single-Port, 40W, IEEE 802.3af/at PSE
Controller with Integrated MOSFET
19-6142; Rev 0; 12/11
Typical Operating Circuit
General Description
The MAX5984 is a single-port, power-sourcing equip-
ment (PSE) power controller designed for use in IEEE
802.3af/at-compliant PSE. This device provides powered
device (PD) discovery, classification, current limit, and
DC and AC load-disconnect detections. The MAX5984
operates automatically without the need for any software
programming and features an integrated power MOSFET
and sense resistor. The device also supports new Class 5
and 2-Event classification for detection and classification
of high-power PDs. The MAX5984 provides up to 40W to
a single port (Class 5 enabled) and still provides high-
capacitance detection for legacy PDs.
The MAX5984 provides input undervoltage lockout
(UVLO), input overvoltage lockout, overtemperature
detection, output voltage slew-rate limit during startup,
and LED status indication.
The MAX5984 is available in a space-saving, 28-pin
TQFN (5mm x 5mm) power package, and is rated for the
extended (-40NC to +85NC) temperature range.
Applications
Single-Port PSE End-Point Applications
Single-Port PSE Power Injectors (Midspan
Applications)
PoE Repeaters
Switches/Routers
Industrial Automation Equipment
Wireless LAN Access Point/WiMAX Base
Stations
Features
S
IEEE 802.3af/at Compliant
S
Up to 40W for Single-Port PSE Applications
S
Integrated 0.5I Power MOSFET and Sense
Resistor
S
2-Event Pin-Select (MAX5984A/MAX5984B)
S
PD Detection and Classification
S
Programmable Current Limit for Class 5 PDs
S
High-Capacitance Detection for Legacy Devices
S
Supports Both DC and AC Load Removal
Detections
S
Current Foldback and Duty Cycle-Controlled
Current Limit
S
LED Indicator for Port Status
S
Direct Fast-Shutdown Control Capability
S
Space-Saving, 28-Pin TQFN (5mm x 5mm)
Package
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
**Future product—Contact factory for availability.
Ordering Information
IEEE is a registered service mark of the Institute of Electrical and Electronics Engineers, Inc.
WiMAX is a registered service mark of WiMAX Forum Corp.
EVALUATION
KIT
AVAILABLE
-54V
AGND
LED
2-EVENT
VEE_DIG
VEE
LEGACY
MIDSPAN
OSC
EN
OUT
OUTP
DET
ILIM1
ILIM2
MAX5984A
PSE OUTPUT
PART
PIN-
SELECT
TEMP RANGE
PIN-
PACKAGE
MAX5984AETI+
2-EVENT -40NC to +85NC 28 TQFN-EP*
MAX5984BETI+** 2-EVENT -40NC to +85NC 28 TQFN-EP*
MAX5984CETI+** PWMEN
-40NC to +85NC 28 TQFN-EP*
MAX5984DETI+
LSCEN
-40NC to +85NC 28 TQFN-EP*