MAX5952AEVKIT Maxim Integrated, MAX5952AEVKIT Datasheet - Page 7

• Manufacturer Part Number: MAX5952AEVKIT
• Description: Power Management IC Development Tools Evaluation Kit/Evaluation System for the MAX5952A
• Manufacturer: Maxim Integrated
• Series: MAX5952r

Specifications of MAX5952AEVKIT

• Product: Controllers & Switches

PD can be located up to 350ft from the EV kit when con-
nected with twisted 4-pair Ethernet cable. The
MAX5952A EV kit provides separate and independent
power control for each of the four Ethernet output ports.
The 10/100BASE-TX voice-over-IP magnetic module is
decoupled to the EV kit’s chassis ground by system
chassis capacitors C19, C20, C21, C22, C24, and C25.
The EV kit’s isolated chassis ground (Chassis_GND) PCB
pad connects to the network system ground.
The MAX5952A EV kit features configurable operational
modes, PD detection, PD classification, overcurrent pro-
tection, current foldback, under/overvoltage protection,
DC and AC disconnect monitoring, high-power mode, and
port current information through the I
overcurrent protection can be programmed through soft-
ware and/or changing current-sense resistors (R1 and
R5), (R2 and R6), (R3 and R7), or (R4 and R8) for the
desired output port. Each of the four modes of operation
(auto, semi, manual, shutdown) can be evaluated after
configuring jumper JU6 and configuring the appropriate
MAX5952A register (see Table 3) or using the software’s
high-level Configuration window. PD detection diodes
D1–D4 can be bypassed to reduce power dissipation
when AC-disconnect monitoring is not required, using
jumpers JU15–JU18. Each port’s AC detection circuit
resistor-capacitor-diode (RCD) network can be reconfig-
ured with a jumper also. See Tables 4, 8, and 9 for various
AC detection disconnect and oscillator configurations.
Each port features a 600W bidirectional overvoltage tran-
sient suppressor, diodes (D9–D12), and decoupling
capacitors (C26–C29) for transient protection at the port.
Test points and jumpers have been provided for voltage
probing and current measurements of each channel’s
power circuit. Additionally, a 6-pin, 0.100in center header is
also provided for monitoring the SHDN1, SHDN2, SHDN3,
SHDN4, and RESET signals routed to the MAX5952A pins
from the respective switch (S1–S5). When using the header
signals, caution should be exercised since DGND and
GND are shorted by resistor R72 PCB shorting trace.
Additionally, since the GND is more positive than VEE, use
an isolated oscilloscope when probing signals, with respect
to VEE. Green LEDs relative to each port’s RJ-45 output
jack, indicate when the respective port’s power is turned on.
A 100Hz oscillator circuit, which meets the IEEE 802.3af
and pre-802.3at PSE power interface (PI) parameters for
AC-disconnect detection, is provided by the MAX5952A EV
kit. Five ICs make up the 100Hz oscillator circuit that con-
sists of U5, a programmable 40MHz EconOscillator/Divider
square-wave oscillator, and the MAX7491 dual universal
switched-capacitor filter, U4. Voltage reference source U6
(MAX6106) provides 2.048V for the circuit and level shifts
the sine wave’s output. The MAX4599, an SPDT analog
switch, and IC U3, the LMX358 dual-output op amps, pro-
MAX5952A Evaluation Kit/Evaluation System
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C interface. The
vide support functions for the oscillator circuit. An external
sine-wave oscillator meeting the IEEE 802.3af and pre-
802.3at PSE PI parameters can be connected to the EV
kit’s BNC connector (OSC_INPUT) after reconfiguring
jumper JU7. The EV kit’s 100Hz oscillator circuit can be
shut down by using jumper JU8 if an external oscillator is
used or AC-disconnect detection is not required.
The EV kit provides optical isolation for the I
3-wire interface required by the MAX5952A, operating as
a slave device by optical couplers U7 and U8. The opti-
cally isolated interface connects to a computer’s USB
port through a CMAXQUSB interface board. The EV kit’s
I
ured for interfacing to a stand-alone microcontroller for
isolated (2-wire) or nonisolated (3-wire) serial operation.
Additionally, for stand-alone microcontroller operation,
the CMAXQUSB interface is not required. A separate
+3.3V power supply capable of supplying 100mA is
required for the MAX5952A optically isolated I
ant 3-wire interface. Note that DGND and GND are short-
ed by a PCB trace between the pads of resistor R72.
The optical isolation consists of optocoupler U7 that provides
galvanic isolation for the serial-interface clock line (SCL) and
serial-interface input data line signals. Optocoupler U8 pro-
vides galvanic isolation for the serial output and data line
(SDAOUT) and INT signals. The SCL and SDAOUT signals’
3-wire serial interface are combined on the isolated 2-wire
side prior to feeding logic buffer U9. The SCL_IN, SDA,
INT_OUT, OPTO_GND, and OPTO_VCC PCB pads are
used for a 2-wire isolated stand-alone operation. For noniso-
lated stand-alone 3-wire operation, jumper JU9 shorting
trace must be cut open and then the SCL, SDAIN, SDAOUT,
INT, DGND, and VDIG PCB pads must be connected to the
microcontroller circuit. Note that the EV kit’s provided VDIG is
at +3.3V. The OPTO_GND and GND, DGND planes are iso-
lated by the optical couplers. However, when using the EV
kit in a nonisolated configuration, caution should be exer-
cised since DGND and GND are shorted by resistor R72
PCB shorting trace. Since GND is more positive than VEE,
use an isolated oscilloscope when probing signals with
respect to VEE.
The MAX5952A slave address is configured by four
jumpers (JU1–JU4) and can be configured from 0x40
through 0x5F hexadecimal serial address. Global
address 0x60 is accepted by the MAX5952A regard-
less of the jumper settings. See Table 1 for more infor-
mation on setting the MAX5952A slave address.
The MAX5952A EV kit features several jumpers to
reconfigure the EV kit for various PSE configurations and
PD requirements. Additionally, jumpers and PCB pads
are provided for connecting an external microcontroller.
2
C-compliant 2-wire or 3-wire interface can be reconfig-
Jumper Selection
2
C-compliant
2
C-compli-
7