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802.3af-compliant/pre-IEEE
802.3at-compatible power-sourcing equipment (PSE).
This device provides powered device (PD) discovery,
classification, current limit, DC and AC load disconnect
detections in compliance with the IEEE 802.3af stan-
dard. The MAX5952 is pin compatible with MAX5945/
LTC4258/LTC4259A PSE controllers and provides addi-
tional features.
The MAX5952 features high-power mode that provides
up to 45W per port. The MAX5952 provides instanta-
neous readout of each port current through the I
2
C inter-
face. The MAX5952 also provides high-capacitance
detection for legacy PDs.
The device features an I
2
C-compatible, 3-wire serial inter-
face, and is fully software configurable and programma-
ble. The class-overcurrent detection function enables
system power management to detect if a PD draws more
than the allowable current. The MAX5952s extensive pro-
grammability enhances system flexibility, enables field
diagnosis, and allows for uses in other applications.
The MAX5952 provides four operating modes to suit dif-
ferent system requirements. Auto mode allows the device
to operate automatically without any software supervision.
Semi-automatic mode automatically detects and classi-
fies a device connected to a port after initial software acti-
vation, but does not power up that port until instructed to
by software. Manual mode allows total software control of
the device and is useful for system diagnostics.
Shutdown mode terminates all activities and securely
turns off power to the ports.
The MAX5952 provides input undervoltage lockout
(UVLO), input undervoltage detection, input overvolt-
age lockout, overtemperature detection, output voltage
slew-rate limit during startup, power-good status, and
fault status. The MAX5952s programmability includes
startup timeout, overcurrent timeout, and load-discon-
nect detection timeout.
The MAX5952 is available in a 36-pin SSOP package and
is rated for both extended (-40癈 to +85癈) and upper
commercial (0癈 to +85癈) temperature ranges.
Applications
Power-Sourcing Equipment (PSE)
Switches/Routers
Midspan Power Injectors
Features
o IEEE 802.3af Compliant/Pre-IEEE 802.3at
Compatible
o Instantaneous Readout of Port Current Through
I
2
C Interface
o High-Power Mode Enables Up to 45W Per Port
o High-Capacitance Detection for Legacy Devices
o Pin Compatible to MAX5945 and
LTC4258/LTC4259A
o Four Independent Power-Switch Controllers
o PD Detection and Classification
o Supports Both DC and AC Load Removal
Detections
o I
2
C-Compatible, 3-Wire Serial Interface
o Current Foldback and Duty-Cycle-Controlled
Current Limit
o Open-Drain INT Signal
o Direct Fast Shutdown Control Capability
High-Power, Quad, PSE Controller
for Power-Over-Ethernet
________________________________________________________________ Maxim Integrated Products   1
19-0858; Rev 1; 1/10
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxims website at www.maxim-ic.com.
Pin Configuration and Selector Guide appear at end of data
sheet.
EV
A
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A
TI
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IT
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VA
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Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX5952AEAX+*
-40癈 to +85癈
36 SSOP
MAX5952AUAX+
0癈 to +85癈
36 SSOP
MAX5952CEAX+*
-40癈 to +85癈
36 SSOP
MAX5952CUAX+*
0癈 to +85癈
36 SSOP
+Denotes a lead(Pb)-free/RoHS-compliant package.
*Future productcontact factory for availability.
IEEE is a registered service mark of the Institute of Electrical
and Electronics Engineers, Inc.