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MAX5995B Evaluation Kit
Evaluates: MAX5995A/B/C/MAX5974D
General Description
The MAX5995 evaluation kit (EV kit) is a fully assembled
and tested surface-mount circuit board featuring an
Ethernet port, network powered-device (PD) interface
controller circuit for -57V supply rail systems. The EV kit
uses the MAX5995B IEEE
®
802.3af/at/bt-compliant
network PD interface controller in a 16-pin TQFN package
with an exposed pad. The IC is used in Power-over-
Ethernet (PoE) applications requiring DC power from
an Ethernet network port for PDs such as VoIP phones,
wireless access nodes, security cameras, lighting, and
building automation.
The EV kit receives power from IEEE 802.3af/at/bt-
compliant power-sourcing equipment (PSE). Refer to
the MAX5952, MAX5965A/MAX5965B, and MAX5980
IC data sheets for PSE controllers. The PSE provides
the required -36V to -57V DC power over an unshielded
twisted-pair Ethernet network cable to the EV kit’s RJ45
magnetic jack. The EV kit features a 1 x 1 Gigabit RJ45
magnetic jack and two active full-wave rectifiers (N101
and N102) for separating the DC power provided by an
endspan or midspan Ethernet system.
The EV kit can also be powered by a wall adapter power
source. The EV kit provides PCB pads to accept the
output of a wall adapter power source. When a wall
adapter power source is detected, it always takes
precedence over the PSE source and allows the wall
adapter to power the EV kit.
The EV kit demonstrates the full functionality of the
IC, such as PD detection signature, PD classification
signature, Multi-Event Classification (MEC), Intelligent
MPS, inrush current control, input undervoltage lockout
(UVLO), and DC-DC step-down converter. The step-down
converter operates at a fixed 290kHz switching frequency
and is configured for an isolated active-clamped forward
topology with output voltage +12V DC that can deliver
5.5A of current.
Features
●
IEEE 802.3af/at/bt-Compliant PD Interface Circuit
●
Multi-Event Classification 0-8
●
-36V to -57V Input Range
●
Demonstrates a 71W PD Design with Isolated Active-
Clamped Forward Topology DC-DC Converter
●
+12V Output at 5.5A
●
Startup Inrush Current Limit of 135mA (typ)
●
Current Limit During Normal Operation
●
Evaluates Endspan and Midspan Ethernet Systems
●
Type 1-4 PSE Classification Indicator
●
Simplified Wall Adapter Interface
●
Demonstrates Sleep and Ultra-Sleep
Power-Saving Modes
●
Proven PCB Layout
●
Fully Assembled and Tested
Ordering Information
appears at end of data sheet.
IEEE is a registered service mark of the Institute of Electrical and Electronics Engineers, Inc.
Warning:
The EV kit is designed to operate with high voltages. Dangerous voltages are present on this EV kit and on equipment
connected to it. Users who power up this EV kit or power the sources connected to it must be careful to follow safety procedures
appropriately to work with high-voltage electrical equipment.
Under severe fault or failure conditions, this EV kit may dissipate large amounts of power, which could result in the mechanical
ejection of a component or of component debris at high velocity. Operate this kit with care to avoid possible personal injury.
319-100275; Rev 0; 11/18
MAX5995B Evaluation Kit
Evaluates: MAX5995A/B/C/MAX5974D
Quick Start
Required Equipment
●
MAX5995_EVKIT_A
●
An IEEE 802.3af/at/bt compliant PSE and
a Category 5e Ethernet network cable
●
-48V, 3A capable DC power supply
●
Voltmeter
The EV kit can also accept power from a wall adapter
power source. When a wall adapter power source is
detected between the POWER+ and POWER- pads, the
IC’s internal isolation switch disconnects, which allows the
wall adapter to supply power to the EV kit.
The EV kit demonstrates the full functionality of the IC
such as PD detection signature, PD classification signa-
ture, Multi-Event Classification (MEC), Intelligent MPS,
inrush current control, and UVLO. Resistor R101 sets the
PD detection impedance. Resistors R44 and R6 set the
PD classification signatures.
The EV kit’s integrated DC-DC step-down converter is
configured for an isolated ACTIVE-CLAMPED forward
converter topology with output voltage of +12V and
provides up to 5.5A at the output while achieving up to
92.5%, 92.4% and 92% efficiencies for 42V/48V/57V
input, respectively. The step-down converter operates at
a fixed 290kHz switching frequency.
Procedure
The EV kit is fully assembled and tested. Follow the steps
below to verify board operation:
Caution: Do not turn on the power supply until all
connections are completed.
1)
Use one of the following methods to power the EV kit:
a)
If network connectivity is required:
Connect a
Category 5e Ethernet network cable from the EV
kit input port RJ45 connector to the correspond-
ing PSE Ethernet LAN connection that provides
power to the EV kit.
b)
If network connectivity is not required:
Connect a -48V DC power supply between the
-54V and GND PCB pads on the EV kit. Connect
the power-supply positive terminal to the GND
pad and the negative terminal to the -54V pad.
2)
3)
Activate the PSE power supply or turn on the external
DC power supply.
Using a voltmeter, verify that the EV kit provides +12V
across the V
OUT
and RTN PCB pads.
PD Class selection by
Classification resistors
By selecting the two external resistors connected to CLSA
and CLSB pins, the power consumption requested by the
PD can be defined.
Table 1
shows the the R
CLSA
and
R
CLSB
resistor values needed to set for PD class and the
PD power consumption defined by standards. R
CLSA
sets
classification current for the 1st and 2nd class Events for
0~4 class PD complaint with IEEE 802.3af/at standard,
and RCLSB set classification current for the 3rd to 5th
class event for 0~8 class PD complaint with IEEE 802.3bt
standard.
Detailed Description of Hardware
(or Software)
The MAX5995 EV kit features an Ethernet port
and network PD interface controller circuit for -57V
supply rail systems. The EV kit contains a IEEE
®
802.3af/
at-compliant network PD interface controller in a 16-pin
TQFN-EP package. The IC is used in PoL applications
for powering PDs from an unshielded twisted-pair (UTP)
Ethernet Category 5e network cable and PSE port using
endspan or midspan Ethernet systems.
The EV kit receives power from an IEEE 802.3af/
at-compliant PSE and a UTP cable connected to the EV
kit’s RJ45 magnetic jack. The EV kit uses a 1 x 1 gigabit
RJ45 magnetic jack and two active full-wave bridge power
rectifiers to separate the -57V DC power sent by the PSE.
The EV kit can accept power from an endspan or midspan
PSE network configuration.
Table 1. PSE Type and PD Class with
Classification Resistor R
CLSA
and R
CLSB
PD CLASS
0
1
2
3
4
5
6
7
8
POWER
REQUESTED BY PD
12.95W
3.84W
6.49W
12.95W
25.5W
38.25W
51W
61W
71W
R
CLSA
619
118
66.5
43.2
30.9
30.9
30.9
30.9
30.9
R
CLSB
OPEN
OPEN
OPEN
OPEN
30.9
619
118
66.5
43.2
IEEE is a registered service mark of the Institute of Electrical and Electronics Engineers, Inc.
www.maximintegrated.com
Maxim Integrated
│
2
MAX5995B Evaluation Kit
Evaluates: MAX5995A/B/C/MAX5974D
Wall Adapter Power Source (POWER+, POWER-)
The EV kit can also accept power from a wall adapter
power source. Use the POWER+ (0V) and POWER-
(-10V to -57V) PCB pads to connect the wall adapter
power source. The wall adapter power source operating-
voltage range must be within +10V to +57V for the EV kit.
When the wall adapter power source is above +10V it
always takes precedence over the PSE source. Once the
wall adapter power source is detected, the IC’s internal
isolation switch disconnects. The wall adapter power is
supplied to V
DD
through diode S210. Once it takes over,
the classification process is disabled.
When the wall adapter power source is below +8V, the
PSE provides power through the IC’s internal isolation
switch. Diode S210 prevents the PSE from back-driving
the wall adapter power source when it is below +8V.
Sleep, Ultra-Sleep Modes and LED Operation
The EV Kit supports operating the MAX5995 in power
saving modes such as the Sleep and Ultra Sleep. By
using the SW3 DIP-switch, the
SL
pin could be driven low
to enter the Sleep mode. The ultra-sleep mode could be
entered by driving both
SL
and
ULP
pin to low (using DIP
switch SW1, SW3). The device could be commanded to
exit sleep or ultra-sleep mode by driving the
WK
pin low
through the switch SW2.
The device features a dedicated LED pin which can be
programmed to source out current when the device is in
MPS, sleep or ultra-sleep modes. Diode named LED con-
nects between LED pin and V
SS
and lights up in green
color to indicate LED current. The magnitude of the LED
current can be controlled as per the value of the R105
resistor connected between the
SL
pin and V
SS
.
Undervoltage Lockout (UVLO)
EV Kit Compliance to MAX5995A, MAX5995C
The EV kit operates up to a -57V supply with a turn-on
UVLO threshold (V
ON
) at -35.4V and a turn-off UVLO
threshold (V
OFF
) at -30.0V. When the input voltage is
above V
ON
, the EV kit is enabled. When the input voltage
goes below V
OFF
, the EV kit is disabled.
By default, the EV kit is installed with MAX5995B IC.
However, the EV kit can also be used to evaluate the
MAX5995A and MAX5995C variants of the IC without
any change in schematic. Do note that for evaluating
MAX5995C, the duty cycle of the MPS current is selectable
through the choice of the resistor R40. This resistor should
not be installed while evaluating MAX5995A, MAX5995B.
www.maximintegrated.com
Maxim Integrated
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MAX5995B Evaluation Kit
Evaluates: MAX5995A/B/C/MAX5974D
Component Suppliers
SUPPLIER
CoilCraft
Comchip
Diodes Incorporated
Emerson Network Power
Fairchild Semiconductor
Kemet
Keystone
Lite-On Electronics
Maxim Integrated
Murata
On Semiconductor
Panasonic
Pulse Electronics
Renesas Technology Group
Samsung Electronics
Stackpole Electronics
Sumida
Taiyo Yuden
TDK
TE Connectivity
Texas Instruments
Vishay Dale
Wurth Elektronik
www.coilcraft.com
www.comchiptech.com
www. diodes.com
www.vertivco.com
www.onsemi.com
www.ir.kemet.com
www.keyelco.com
www. us.liteon.com
www.maximintegrated.com
www.murata .com
www.onsemi.com
www.panasonic.com
www.pulseelectronics.com
www.renesas.com
www.samsung.com
www.seielect.com
www.sumida.com
www.yuden.co.jp
www.us.tdk.com
www.te.com
www.ti.com
www.vishay.com
www.we-online.com
WEBSITE
Note:
Indicate that you are using the MAX5995 when contacting these component suppliers.
Ordering Information
PART
MAX5995BEVKIT#
#Denotes
RoHS compliant.
TYPE
EVKIT
www.maximintegrated.com
Maxim Integrated
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4
MAX5995B Evaluation Kit
Evaluates: MAX5995A/B/C/MAX5974D
MAX5995B EV Kit Bill of Materials
PART
C1
QTY
1
DESCRIPTION
1µF ±10%, 16V X7R ceramic
capacitor (0805)
Murata GRM21BR71C105KA01
100pF ±5%, 50V C0G ceramic
capacitor (0603)
Murata GRM1885C1H101JA01
0.047µF ±10%, 50V X7R
ceramic capacitor (0603)
Tdk CGA3E2X7R1H473K080AA
0.01µF ±5%, 50V X7R ceramic
capacitor (0603)
Kemet C0603C103J5RAC
1µF ±10%, 16V X7R ceramic
capacitor (0603)
Taiyo Yuden EMK107B7105KA
2.2µF ±10%, 100V X7R ceramic
capacitor (1210)
Murata GRM32ER72A225KA35
0.047µF ±10%, 500V X7R
ceramic capacitor (1206)
Vishay Vitramon VJ1206Y473KXEAT5Z
0.1µF ±10%, 50V X7R ceramic
capacitor (0603)
Murata GCJ188R71H104KA12
220pF ±10%, 250V X7R ceramic
capacitor (0603)
Murata GRM188R72E221K
1000pF ±10%, 250V X7R ceramic
capacitor (2211)
Murata GA352QR7GF102KW01)
100µF ±20%, 16V X7R tantalum
capacitor (7343)
Panasonic 16TQC100MYF
22µF ±10%, 16V X5R ceramic
capacitor (1206)
Samsung Electronics CL31A226KOCLFN
33µF ±20%, 100V aluminium
electrolytic capacitor (Case G)
Panasonic EEE-FK2A330P
4700pF ±10%, 50V X7R ceramic
capacitor (0603)
Murata GRM188R71H472KA01
PART
C41
QTY
1
DESCRIPTION
2200pF ±10%, 50V X7R ceramic
capacitor (0603)
Murata GRM39X7R222K50V
2200pF ±10%, 2000V X7R ceramic
capacitor (1206)
Kemet C1206X222KGRAC
0.1µF ±10%, 100V X7R ceramic
capacitor (0805)
Murata GRM21BR72A104KAC4
0.1µF ±10%, 100V X7R ceramic
capacitor (0603)
Murata GCJ188R72A104KA01
0.068µF ±5%, 100V C0G ceramic
capacitor (1206)
Tdk CGA5L1C0G2A683J160
Schottky Diode, 100V, 2A,
SMB Comchip CDBB2100-G
Diode, 250V, 0.25A, SOD-323 Diodes
Incorporated BAV21WS-7-F
Zener Diode, 10V, 0.005A, SOD-323
Diodes Incorporated BZT52C10S-7-F
Zener Diode, 16V, 0.005A, SOD-323
Diodes Incorporated BZT52C16S-7-F
Rectifier bridge diode, 100V, 1.5A,
SMT Diodes Incorporated DF1501S
TVS Diode, 120V, 2A, SMA Diodes
Incorporated SMAJ120A-13-F
Zener Diode, 18V, 0.05A, SOD-323
Diodes Incorporated BZT52C18S-7-F
TVS Diode, 58V, 100A, SMB Diodes
Incorporated SMBJ58A-13-F
Schottky Diode, 100V, 2A,
SMT Fairchild Semiconductor S210
Zener Diode, 12V, 0.005A, SOD-323
On Semiconductor MM3Z12VT1G
Standoff, 1/2 Inch, Female-Threaded,
Hex, Aluminium Generic Part 2203
Phillips machine screw, 1/4 Inch,
Stainless Steel Mcmaster-Carr;
Keystone; Mcmaster-Carr 4C25MXPS;
9900;91772A106
C2, C11,
C31, C36
C3, C5,
C10
4
C45
1
3
C56-C59
4
C4, C32
2
C93, C105
2
C6
1
C101
D2, D3,
D6, D7
D9, D10,
D12-D15
D11
D16
D17, D18
D19
D20
D101
D103
D105-D108
H1-H4
1
C7, C8,
C13
3
4
6
1
1
2
1
1
1
1
4
4
C14
1
C15, C23,
C25
3
C19
C21, C22,
C24, C33,
C60
C26
1
5
1
C27-C30,
C34
5
C38
1
C39
1
H5-H8
4
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Maxim Integrated
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