Texas Instruments TPS23881EVM User manual

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TPS23881EVM: PoE, PSE, TPS23881 Evaluation Module
User's Guide
SLVUBP0A–May 2019–Revised August 2019
TPS23881EVM: PoE, PSE, TPS23881 Evaluation Module
This user’s guide describes the evaluation modules (EVM) for the TPS23881 (TPS23881EVM-008 and
BOOST-PSEMTHR-007). The EVM contains evaluation and reference circuitry for the TPS23881. The
TPS23881 is a Power-over-Ethernet (PoE) device for power sourcing equipment (PSE).
Contents
1 Description.................................................................................................................... 2
2 Quick Start.................................................................................................................... 2
3 General Use Features....................................................................................................... 6
4 TPS23881 Autonomous Operations ...................................................................................... 8
5 TPS23881EVM GUI Setup ................................................................................................. 8
6 EVM Schematic, Layout Guidelines, PCB Assembly and Layer Plots.............................................. 17
7 Bill of Materials ............................................................................................................. 28
List of Figures
1 Basic Setup Using USB2ANY ............................................................................................. 4
2 Advanced Setup Using LaunchPad™ .................................................................................... 5
3 TPS23881EVM GUI Start-up Window ................................................................................... 9
4 TPS23881EVM GUI Load Firmware 1 .................................................................................. 10
5 TPS23881EVM GUI Load Firmware 2 .................................................................................. 10
6 Device Configuration and Port Telemetry Page ....................................................................... 11
7 Register Map ............................................................................................................... 12
8 Program Started............................................................................................................ 13
9 Terminal Response With Connected Ports............................................................................. 14
10 Auto Mode System Software Structure.................................................................................. 16
11 Semi Auto Mode System Software Structure........................................................................... 17
12 BOOST-PSEMTHR-007 (Motherboard) Schematic: Control ......................................................... 18
13 BOOST-PSEMTHR-007 (Motherboard) Schematic: Power Ports................................................... 19
14 TPS23881EVM-008 (Daughterboard) Schematic...................................................................... 20
15 BOOST-PSEMTHR-007 (Motherboard) Top Side Assembly......................................................... 21
16 BOOST-PSEMTHR-007 (Motherboard) Top Side Routing........................................................... 22
17 BOOST-PSEMTHR-007 (Motherboard) Layer 2 Routing............................................................. 23
18 BOOST-PSEMTHR-007 (Motherboard) Layer 3 Routing............................................................. 24
19 BOOST-PSEMTHR-007 (Motherboard) Bottom Side Routing ....................................................... 25
20 TPS23881EVM-008 (Daughterboard) Top Side Assembly........................................................... 26
21 TPS23881EVM-008 (Daughterboard) Top Side Routing ............................................................. 26
22 TPS23881EVM-008 (Daughterboard) Bottom Side Routing ......................................................... 26
23 TPS23881EVM-008 (Daughterboard) Bottom Side Assembly ....................................................... 27
List of Tables
1 TPS23881EVM Voltage Rail Current Requirements ................................................................... 3
2 EVM Input/Output Connectors............................................................................................. 6
3 EVM LEDs.................................................................................................................... 6
4 EVM Test Points............................................................................................................. 7

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5 EVM Jumpers ............................................................................................................... 7
6 AUTO Pin Programming.................................................................................................... 8
7 BOOST-PSEMTHR-007 Bill of Materials ............................................................................... 28
8 TPS23881EVM-008 Bill of Material...................................................................................... 30
Trademarks
LaunchPad, Code Composer Studio are trademarks of Texas Instruments.
All other trademarks are the property of their respective owners.
1 Description
The TPS23881EVM features the 8-channel, TPS23881 and IEEE 802.3bt (draft) PoE PSE controller. The
EVM consists of a motherboard (BOOST-PSEMTHR-007) and a daughterboard (TPS23881EVM-008)
containing one TPS23881 device. The TPS23881EVM provides a multi-port base platform interface for
TPS23881EVM-008, MSP-EXP430FR5969 (LaunchPad™), and USB2ANY (USB Interface Adapter).
1.1 Features
The EVM supports the following features:
• Four IEEE802.3bt 2-pair ports with 1000BASE-T (gigabit Ethernet data pass-through)
• Two IEEE802.3bt 4-pair ports with 1000BASE-T (gigabit Ethernet data pass-through)
• Single DC power supply input
• Onboard 3.3-V regulator
• Onboard I2C interface to both TPS23881 devices from either USB2ANY or MSP-EXP430FR5969.
• Port ON status LEDs
• User test points
1.2 Applications
The EVM is used in the following applications:
• Enterprise and SoHO switches and routers
• Connected ceiling LED switches
• PoE pass-through power modules
• Network video recorders (NVRs)
• Wireless backhaul and small-cell networking
2 Quick Start
2.1 Input Power
2.1.1 Input Power (Labeled VPWR)
The DC input voltage is provided through J1 (screw jack). A DC power supply or wall adapter with
sufficient current capacity can power the EVM.
CAUTION
Reverse voltage protection is not provided; ensure that the correct polarity is
applied to J1.
This DC input is labeled VPWR in the schematics and is used for port VBUS as well as for the TPS23881
devices. The VPWR connections to the PoE ports are not fused. Each two-pair port is capable of
furnishing at least 30 W and each four-pair port can furnish 90 W.

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The minimum PSE port voltage is 44 VDC for type 1, 50 V for type 2 and type 3, and 52 V for type 4.
During evaluation, choose the appropriate DC power supply for different environments.
2.1.2 Local 3.3 V (Labeled 3.3 V)
Local 3.3 V for local devices (labeled as 3.3 V) is provided by the onboard LM5019 buck converter. The
LM5019 provides a basic power-on sequence and provides a well-controlled and consistent start-up. In
addition to 54 V, the TPS23881 requires 3.3 V for the digital circuitry and this is routed up to
TPS23881EVM-008 over the connector interface. The current consumption is 6-mA typical and 12-mA
maximum.
2.1.3 External 3.3 V (Labeled 3.3 V_USB)
The BOOST-PSEMTHR-007 provides galvanic isolation between the PoE power side and host side using
digital isolators (ISO7241CD). The host side power is provided either from J2 (from USB2ANY) or J5 (from
MSP-EXP430FR5969).
CAUTION
Do not use USB2ANY and LaunchPad simultaneously.
Table 1. TPS23881EVM Voltage Rail Current Requirements
VOLTAGE RAIL TYPICAL (mA) MAXIMUM (mA)
3.3 V_USB 2.5 3
3.3 V 6 12
VPWR (Miscellaneous) 35 57
VPWR (4 × 2 Pair Ports and 2 × 4 pair Ports) 5556 5578
VPWR Total (4 × 2 Pair Ports and 2 × 4 pair Ports) 5591 5613
2.2 PoE Port Interfaces
The TPS23881 device must be configured through the host to become operational. This EVM provides
two ways to control the TPS23881: TPS238x EVM GUI (with USB2ANY) and MSP-EXP430FR5969
LaunchPad.
2.2.1 IEEE802.3bt 2-Pair Ports
Four 2-pair ports are provided at J19, J20, J8, and J7 for 2-pair ports 1, 2, 3, and 4, respectively. The
power furnished is according to alternative A with MDI-X polarity.
2.2.2 IEEE802.3bt 4-Pair Ports
Two 4-pair high power ports are provided at J21 and J9 for 4-pair ports 1 and 2, respectively. The power
furnished is according to alternative A with MDI-X polarity and alternative B with S polarity on a single port
connector. A single- or dual-signature PD may be powered by the 4-pair ports with proper port
configuration (enabling 4-pair mode).
2.3 I2C Interfaces
Two I2C interfaces to the TPS23881 are provided on the EVM.
2.3.1 USB2ANY
J2 provides an interface with the USB2ANY adapter when using a PC and GUI.

TPS2373-4EVM-758
Class 3-4
Power
Supply
J7
J1
J21
J9
TPS23881EVM-008
(+)
(-)
J8
J20 J19
D1
J2
USB2ANY
BOOST-PSEMTHR-007
TPS2373-4EVM-758
Class 5-8
PC
USB Cable
Ethernet
Cable Ethernet Cable
Positive Negative
Ribbon
Cable
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2.3.2 MSP-EXP430FR5969
J3, J4, and J5 provide an interface with the MSP-EXP430FR5969 when using a PC to develop custom
system software.
2.4 Basic Test Setup Using USB2ANY for I2C Interface (Auto Mode or Semi-Auto Mode
Operation with I2C Monitoring)
An I2C interface is provided through J2 to the TPS23881 devices on the TPS23881EVM-008. The
USB2ANY adapter (not included) can be used with any TI GUI which uses USB2ANY to read and write
over an I2C bus. Figure 1 illustrates the basic setup using USB2ANY.
Figure 1. Basic Setup Using USB2ANY
CAUTION
If a jumper is installed on J5, DC power supply needs to be on before turning
on TPS2388xEVM GUI and starting I2C communication.

TPS2373-4EVM-758
Class 3-4
Power
Supply
J7
J1
J21
J9
TPS23881EVM-008
(+)
(±)
J8
J20 J19
D1
J2
BOOST-PSEMTHR-007
MSP-
EXP430FR5969
TPS2373-4EVM-758
Class 5-8
PC
USB Cable
Ethernet
Cable Ethernet Cable
Positive Negative
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2.5 Advanced Test Setup Using MSP-EX430FR5969 LaunchPad™
The LaunchPad (not included) running a custom software program can communicate with the TPS23881
devices on the TPS23881EVM-008. Figure 2 shows the advanced setup using LaunchPad.
Figure 2. Advanced Setup Using LaunchPad™
CAUTION
If a jumper is installed on J5, DC power supply needs to be on before
connecting MSP430 LaunchPad to PC and starting I2C communication.

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3 General Use Features
3.1 EVM Input/Output Connectors and Switches
Table 2 lists the EVM input and output connectors.
Table 2. EVM Input/Output Connectors
CONNECTOR
OR SWITCH LABEL DESCRIPTION
J1 J1 DC power supply screw jack. (44–57 VDC). Use a 48 VDC (nominal) for type 1 and 54 VDC
(nominal) for type 2, 3, and 4 PSE operation.
J2 J2 Ribbon cable connection to USB2ANY adapter
J3 J3 LaunchPad control (mates with LaunchPad J1)
J4 J4 LaunchPad I2C (mates with LaunchPad J2)
J5 J5 LaunchPad power (onboard, mates with LaunchPad J6)
J6 J6 TPS23881EVM-008 control (mates with TPS23881EVM-008 J3)
J17 J17 TPS23881EVM-008 Channel 5–8 (mates with TPS23881EVM-008 J2)
J18 J18 TPS23881EVM-008 Channel 1–4 (mates with TPS23881EVM-008 J1)
J22 J22 Two-pair port 1 data only
J19 2 Pair Port 1 Two-pair port 1 power and data
J23 J23 Two-pair port 2 data only
J20 2 Pair Port 2 Two-pair port 2 power and data
J11 J11 Two-pair port 3 data only
J8 2 Pair Port 3 Two-pair port 3 power and data
J10 J10 Two-pair port 4 data only
J7 2 Pair Port 4 Two-pair port 4 power and data
J24 J24 Four-pair port 1 data only
J21 4 Pair Port 1 Four-pair port 1 power and data
J12 J12 Four-pair port 2 data only
J9 4 Pair Port 2 Four-pair port 2 power and data
J29 J29 Chassis ground tie point
3.2 EVM LEDs
Table 3 lists the EVM LEDs and their descriptions.
Table 3. EVM LEDs
LED COLOR LABEL DESCRIPTION
D1 GREEN 48 V 48-V ON indicator
D16 BLUE D13 Two-pair port 1 power is ON. For J19 supplier #1 (see the bill of materials (BOM)), J19 internal port
LED is active. For supplier #2, D16 is active.
D17 BLUE D15 Two-pair port 2 power is ON. For J20 supplier #1 (see the BOM), J20 internal port LED is active. For
supplier #2, D17 is active.
D13 BLUE D14 Two-pair port 3 power is ON. For J8 supplier #1 (see the BOM), J8 internal port LED is active. For
supplier #2, D13 is active.
D12 BLUE D12 Two-pair port 4 power is ON. For J7 supplier #1 (see the BOM), J7 internal port LED is active. For
supplier #2, D12 is active.

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3.3 EVM Test Points
Table 4 lists and describes the EVM test points.
Table 4. EVM Test Points
TP COLOR LABEL DESCRIPTION
Motherboard: BOOST-PSEMTHR-007
TP1 RED VPWR Used for VPWR
TP2 RED 3.3 V Used for TPS23881 VDD
TP3 SMT GND VPWR ground
TP4 WHT SDA I2C Data from LaunchPad and USB-TO-GPIO
TP5 WHT SCL I2C Clock from LaunchPad and USB-TO-GPIO
TP6 WHT PSE_SDAO I2C data out from TPS23881
TP7 WHT PSE_SCL I2C clock to TPS23881
TP8 WHT PSE_SDAI I2C data in to TPS23881
TP9 BLK GND1 Ground from LaunchPad and USB2ANY
TP11 SMT TP11 Chassis ground test point
TP14 SMT GND VPWR ground test point
TP15 SMT GND VPWR ground test point
TP16 SMT GND VPWR ground test point
Daughterboard: TPS23881EVM-008
TP2 RED 2P4D Two-pair port 4 DRAIN
TP3 WHT 2P4G Two-pair port 4 GATE
TP4 WHT 4P1AG Four-pair port 1A GATE
TP5 RED 4P1AD Four-pair port 1A DRAIN
TP7 WHT 4P1BG Four-pair port 1B GATE
TP6 RED 4P1BD Four-pair port 1B DRAIN
TP1 BLK GND VPWR ground
TP8 SMT GND VPWR ground
3.4 EVM Test Jumpers
The EVM is equipped with shunts on the jumper positions identified in Table 5, in the Default Pin Position
column. Shunts can be moved and removed, as required, during use.
Table 5. EVM Jumpers
JUMPER DEFAULT PIN
POSITION LABEL DESCRIPTION
Motherboard: BOOST-PSEMTHR-007
J27 1-2 P1 Two-pair port 1 LED bias
J28 1-2 P2 Two-pair port 2 LED bias
J16 1-2 P3 Two-pair port 3 LED bias
J15 1-2 P4 Two-pair port 4 LED bias
J26 1-2 P5 Four-pair port 1A LED bias
J25 1-2 P6 Four-pair port 1B LED bias
J14 1-2 P7 Four-pair port 2A LED bias
J13 1-2 P8 Four-pair port 2B LED bias
Daughterboard: TPS23881EVM-008
J4 1-2;3-4;5-6;7-8 A1;A2;A3;A
4I2C A1-A4 address lines
J5 Open NA AUTO pin selection(autonomous mode is enabled if
connecting auto pin to ground with selected resistance )

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4 TPS23881 Autonomous Operations
The TPS23881 supports autonomous mode which means it can operate in standalone mode without any
host control. In order to enable this function, a pulldown resistor is needed on AUTO pin. During power up,
the resistance on the AUTO pin is measured, and the device is pre-configured according to Table 6 and
all ports are configured with the same power application.
If AUTO pin resistor is selected for 2-pair operation, due to the hardware configuration on the mother
board, only 2-pair ports (J19, J20, J8, J7) are interoperable with PDs. If AUTO pin resistor is selected for
4-pair operation, only 4-pair ports (J21,J9) are interoperable with PDs.
Table 6. AUTO Pin Programming
AUTO PIN AUTONOMOUS MODE
CONFIGURATION RESULTING REGISTER CONFIGURATIONS
Register 0x12h Register 0x14h Register 0x29h
Open/Floating Disabled 0x00h 0x00h 0x00h
124 kΩ2-pair 15 W 0xFFh 0xFFh 0x00h
62 kΩ2-pair 30 W 0xFFh 0xFFh 0x33h
35.7 kΩ4-pair 30 W 0xFFh 0xFFh 0xBBh
22.6 kΩ4-pair 45 W 0xFFh 0xFFh 0xCCh
15.8 kΩ4-pair 60 W 0xFFh 0xFFh 0xDDh
11 kΩ4-pair 75 W 0xFFh 0xFFh 0xEEh
7.7 kΩ4-pair 90 W 0xFFh 0xFFh 0xFFh
5 TPS23881EVM GUI Setup
5.1 TPS23881EVM GUI Installation
TI's TPS23881EVM GUI is used with the TPS23881EVM to control the port and provide real-time
feedback on port telemetry. Download the TPS23881EVM GUI from the TPS23881 product folder page in
the Tools and software section.
Follow the onscreen instructions to complete the installation. The TPS23881 GUI uses the USB2ANY as
an interface between the PC USB port and the BOOST-PSEMTHR-007 J2 connector (I2C interface).
Before starting the TPS23881 GUI, make sure the USB2ANY is properly connected to TPS23881EVM and
the EVM is supplied with a 44-V to 57-V power supply as shown in Figure 1.
5.2 TPS23881EVM GUI Operation
Start the TPS23881EVM GUI by double clicking the GUI icon. A window similar to Figure 3 will come up.

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Figure 3. TPS23881EVM GUI Start-up Window
The default device address in the GUI is set to 0x20 which matches the default configuration of the EVM
(J4 on the daughter card is installed with jumpers). The GUI sets the TPS23881 in configuration B mode
(see the GENERAL MASK Register section of the data sheet for details). The address can be programed
through the A1 to A4 pins and the I2C address setting in the GUI needs to match the hardware
configuration. See the Pin Status Register section of the data sheet for details. The startup page contains
links to the EVM user's guide, TPS23881 data sheet, E2E forum and MSP430 reference code. Four
popular PD end-equipment images are connected to the PSE switch. Links to the recommended PD
device for each end equipment are also provided.
Once the TPS23881 device is connected, click Firmware to select "Reset Factory Firmware" which loads
0x03 version of firmware to TPS23881. If wanting to load a different version of firmware, click "Load
Firmware" and choose SRAM code as desired.

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Figure 4. TPS23881EVM GUI Load Firmware 1
Figure 5. TPS23881EVM GUI Load Firmware 2

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Once firmware is successfully loaded and Device Connected displays and port configuration type is
selected, click Engineering View.
On the page displayed in Figure 6, each port can be configured separately by clicking each RJ45
connector. By default, the TPS23881 is configured in OFF Mode. Each port can be configured by clicking
the RJ45 icon. Clicking the SET ALL PORTS TO STANDARD button sets all port to standard
configurations (configuring ports in Semi-Auto mode, enabling OSS, power policing, and DC disconnect).
Clicking the SET ALL PORTS TO AUTO MODE button enables Auto Mode for all ports.
The status of each port is shown on the configuration and telemetry page. The configuration of the ports
can also be edited on this page by clicking the RJ45 connector.
If the port is configured in Auto Mode, the port will turn on automatically by the PSE device after
connecting a valid PD. If not configured in Auto Mode, a port enable command is required (4P Enable for
4 pair ports and 2P Enable for 2-pair ports). The port can be turned on only when the PD has valid
detection and classification results.
Figure 6. Device Configuration and Port Telemetry Page
The GUI also provides access to every register of the device in the register map.

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Figure 7. Register Map

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5.3 MSP-EXP430FR5969 Details
The TPS23881EVM accepts the MSP-EXP430FR5969 evaluation module when the application requires
management of the TPS23881 devices with an external controller.
1. Install MSP-EXP430FR5969 onto BOOST-PSEMTHR-007 and ensure that the USB2ANY ribbon cable
is NOT installed into J2.
2. Connect the PC to the LaunchPad as shown in Figure 2.
3. The source code was developed for the MSP430 LaunchPad Development Kit (MSP-
EXP430GFR5969) using the Code Composer Studio™ (CCS) version 7.2.0 development environment.
The target MSP430 can be programmed within this environment.
4. Once CCS is installed, use the basic set of instructions listed in Section 5.3.1 to import, build, and run
the project. CCS version 7.2.0 is used in the following examples. Note that a terminal program such as
HyperTerminal or Teraterm is required to view the output from the EVM when it is running.
5.3.1 Basic CCS and Terminal Setup
Use the following steps for basic CCS and terminal setup:
1. Launch the CCS program on the PC: Start →Texas Instruments →Code Composer Studio 7.2.0 →
Code Composer Studio 7.2.0.
2. OK the workspace location and CCS starts.
3. Import the project: Project→Import CCS Projects (make sure you are in CCS Edit mode).
4. Navigate to the project location, then click the Finish button.
5. Build the project by clicking the hammer symbol.
6. Launch the debug session from CCS to activate the current project: Run, Debug (or F11).
7. Run the active project: Run, Resume (or play button, F8).
8. Determine the PC COM port connected to the LaunchPad by going into the Device Manager Ports
(COM and LPT) section. Launch the terminal program.
9. Once the terminal program is properly connected to the LaunchPad running the PoE firmware, then
text similar to the following image appears.
Figure 8. Program Started

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10. The TPS23881EVM is now waiting for a PD load to be installed. As ports are installed, the system
automatically detects, classifies, and powers up the port as shown in Figure 9. Port status is updated
on the screen approximately every 10 seconds.
Figure 9. Terminal Response With Connected Ports

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5.4 MSP430 Reference Code
5.4.1 Overview
There are two versions of MSP430 reference code published on ti.com. One is for basic applications and
the other is focused on multi-port power management applications. The reference code for multi-port
power management applications will be discussed in detail since it has more flexibility and complexity.
The system software supports the following features:
• IEEE802.3bt PoE specification
• Device detection, connection check, and classification
• Automatic power on (standard 2-pair and 4-pair PDs)
• DC disconnect
• Port telemetry updates
• Multi-port power management
The MSP430 communicates with the PC through UART, reporting the parameter and status of the port.

Initialize
MSP430
(GPIO, I2C,UART)
Set ports to Auto mode
Configure interrupts
Enable DC Disconnect
Start Every 10
seconds
Print input voltage, temp, and port
telemetry via UART
(QDEOHDOOSRUWV¶GHWHFWLRQ&
classification
Load SRAM Code
Power off all ports
Configure 2 pair/4 pair mode for
each RJ45 port
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5.4.2 Auto Mode
Auto mode operation is demonstrated in the MSP430 reference code and Figure 10 shows the flow chart.
Basically, after configuration, the TPS23881 handles port detection, classification, turn on, and faults by
itself and there is no control needed from the host.
Figure 10. Auto Mode System Software Structure

Initialize
MSP430
Set Power Off to all ports.
Set Ports to SEMI_AUTO mode
Configure Interrupts, Remapping,
OSS,etc.
Start
Every 10 seconds
Print input voltage, temp, and port
telemetry via UART
Disconnection Event
Get Disconnect
Status
Determine port(s)
Classification Event
Get Classification
Status
Determine port(s)
Power On Port/
PPM
Classification Valid?
Print Status
Fault Event
Get Fault Status
Determine port(s)
Print Status
(QDEOH3RUWV¶GHWHFWLRQ&
classification
Load SRAM Code
Yes
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5.4.3 Semi Auto Mode
Operation, the semi auto mode reference code is interrupt based. When MSP430 receives an interrupt
from the INT pin of the PSE, the code checks interrupt the register and event registers to proceed with
actions accordingly. The flowchart of semi auto mode code is shown in Figure 11.
Figure 11. Semi Auto Mode System Software Structure
6 EVM Schematic, Layout Guidelines, PCB Assembly and Layer Plots
This section contains the TPS23881EVM schematic, layout guidelines, printed-circuit board (PCB)
assembly and layer plots.
6.1 Schematic
Figure 12 through Figure 14 illustrate the TPS23881EVM (daughter card+motherboard) schematics.

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Figure 12. BOOST-PSEMTHR-007 (Motherboard) Schematic: Control

PSE_N3
PSE_N1
J27
P1
J28
P2
J15
P4
J16
P3
5
4
1
2
3
6
7
8
9
10
J18
22V
D9
22V
D6
22V
D5
1:1
1:1
1:1
1:1
22nF
75
22nF
75
22nF
75
22nF
75
1nF
2kV
MDCT3
1
MD3-
2
MD3+
3
MD2+
4
MD2-
5
MDCT2
6
MDCT4
7
MD4+
8
MD4-
9
MD1-
10
MD1+
11
MDCT1
12
13
14
15
16
VDC1+
17
VDC1-
18
VDC2+
19
VDC2-
20
Yellow
Green
Green
Shield GND
1 MX1+
2 MX1-
3 MX2+
6 MX2-
4 MX3+
5 MX3-
7 MX4+
8 MX4-
J19
2 Pair Port 1
PSE_N2
1:1
1:1
1:1
1:1
22nF
75
22nF
75
22nF
75
22nF
75
1nF
2kV
MDCT3
1
MD3-
2
MD3+
3
MD2+
4
MD2-
5
MDCT2
6
MDCT4
7
MD4+
8
MD4-
9
MD1-
10
MD1+
11
MDCT1
12
13
14
15
16
VDC1+
17
VDC1-
18
VDC2+
19
VDC2-
20
Yellow
Green
Green
Shield GND
1 MX1+
2 MX1-
3 MX2+
6 MX2-
4 MX3+
5 MX3-
7 MX4+
8 MX4-
J20
2 Pair Port 2
1:1
1:1
1:1
1:1
22nF
75
22nF
75
22nF
75
22nF
75
1nF
2kV
MDCT3
1
MD3-
2
MD3+
3
MD2+
4
MD2-
5
MDCT2
6
MDCT4
7
MD4+
8
MD4-
9
MD1-
10
MD1+
11
MDCT1
12
13
14
15
16
VDC1+
17
VDC1-
18
VDC2+
19
VDC2-
20
Yellow
Green
Green
Shield GND
1 MX1+
2 MX1-
3 MX2+
6 MX2-
4 MX3+
5 MX3-
7 MX4+
8 MX4-
J8
2 Pair Port 3
PSE_N4
1:1
1:1
1:1
1:1
22nF
75
22nF
75
22nF
75
22nF
75
1nF
2kV
MDCT3
1
MD3-
2
MD3+
3
MD2+
4
MD2-
5
MDCT2
6
MDCT4
7
MD4+
8
MD4-
9
MD1-
10
MD1+
11
MDCT1
12
13
14
15
16
VDC1+
17
VDC1-
18
VDC2+
19
VDC2-
20
Yellow
Green
Green
Shield GND
1 MX1+
2 MX1-
3 MX2+
6 MX2-
4 MX3+
5 MX3-
7 MX4+
8 MX4-
J7
2 Pair Port 4
GND
47µF
C16
Port4_Date1_N
Port4_Date2_P
Port4_Date2_N
Port4_Date3_P
Port4_Date3_N
Port4_Date4_P
Port4_Date4_N
Port3_Date2_P
Port3_Date2_N
Port3_Date3_P
Port3_Date3_N
Port3_Date4_P
Port3_Date4_N
Port1_Date3_P
Port1_Date3_N
Port1_Date4_P
Port2_Date2_N
Port2_Date3_P
Port2_Date4_P
Port2_Date4_N
GND
VPWR
PSE_N1
PSE_N2
PSE_N3
PSE_N4
VPWR VPWR
VPWR
VPWR
GND
PSE_N1
PSE_N4 PSE _N3
PSE_N2
2
3
4
1
5
6
7
8
J10
Port4 Data
2
3
4
1
5
6
7
8
J11
Port3 Data
2
3
4
1
5
6
7
8
J23
Port2 Data
2
3
4
1
5
6
7
8
J22
Port1 Data
J14
P7
J13
P8
22V
D7 22V
D4
PSE_N7
PSE_N8
Port8&7_Data2_N
VPWR
PSE_N7
PSE_N8
2
3
4
1
5
6
7
8
J12
Port8&7 Data
GND
J25
P6
J26
P5
22V
D11
22V
D8
PSE_N5
PSE_N6
Port6&5_Data2_N
Port6&5_Data3_P
Port6&5_Data3_N
Port6&5_Data4_P
Port6&5_Data4_N
PSE_N5
PSE_N6
2
3
4
1
5
6
7
8
J24
Port6&5 Data
5
4
1
2
3
6
7
8
9
10
J17
GND
47µF
C15
GND
VPWR
PSE_N5
PSE_N6
PSE_N7
PSE_N8
VPWR
Port3_Date1_N
Port3_Date1_PPort4_Date1_P
Port1_Date4_N
Port1_Date2_N
Port1_Date2_P
Port1_Date1_N
Port1_Date1_P Port2_Date1_P
Port2_Date1_N
Port2_Date2_P
Port2_Date3_N
Port8&7_Data4_N
Port8&7_Data4_P
Port8&7_Data3_P
Port8&7_Data1_P
Port8&7_Data2_P
Port8&7_Data3_N
Port8&7_Data1_N
Port6&5_Data1_P
Port6&5_Data1_N
Port6&5_Data2_P
22V
D10
TPS23880EVM-008 Port 1-4
TPS23880EVM-008 Port 5-8
2 Pair Port 4 (IEEE802.3at Type 2) 2 Pair Port 3 (IEEE802.3at Type 2)
2 Pair Port 1 (IEEE802.3at Type 2) 2 Pair Port 2 (IEEE802.3at Type 2) 4 Pair Port 1 (Dual IEEE802.3at Type 2)
4 Pair Port 2 (Dual IEEE802.3at Type 2)
TP12
GND
TP13
GND
GND GND
EARTH
EARTH
TP11
GND
J29
7693
2200pF
2000V
C18
2200pF
2000V
C17
1:1
1:1
1:1
1:1
22nF
75
22nF
75
22nF
75
22nF
75
1nF
2kV
MDCT3
1
MD3-
2
MD3+
3
MD2+
4
MD2-
5
MDCT2
6
MDCT4
7
MD4+
8
MD4-
9
MD1-
10
MD1+
11
MDCT1
12
13
14
15
16
VDC1+
17
VDC1-
18
VDC2+
19
VDC2-
20
Yellow
Green
Shield GND
1 MX1+
2 MX1-
3 MX2+
6 MX2-
4 MX3+
5 MX3-
7 MX4+
8 MX4-
J21
1:1
1:1
1:1
1:1
22nF
75
22nF
75
22nF
75
22nF
75
1nF
2kV
MDCT3
1
MD3-
2
MD3+
3
MD2+
4
MD2-
5
MDCT2
6
MDCT4
7
MD4+
8
MD4-
9
MD1-
10
MD1+
11
MDCT1
12
13
14
15
16
VDC1+
17
VDC1-
18
VDC2+
19
VDC2-
20
Yellow
Green
Shield GND
1 MX1+
2 MX1-
3 MX2+
6 MX2-
4 MX3+
5 MX3-
7 MX4+
8 MX4-
J9
Blue
D12
Blue
D13
Blue
D15
Blue
D14
35.7k
R15
35.7k
R16
35.7k
R14
35.7k
R17
35.7k
R20
35.7k
R19
35.7k
R22
35.7k
R21
www.ti.com EVM Schematic, Layout Guidelines, PCB Assembly and Layer Plots
19
SLVUBP0A–May 2019–Revised August 2019
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TPS23881EVM: PoE, PSE, TPS23881 Evaluation Module
Figure 13. BOOST-PSEMTHR-007 (Motherboard) Schematic: Power Ports

Kelvin to U1-4
Kelvin to U1-11 Kelvin to U1-39
Kelvin to U1-32
GND GND
GND GND
2 Pair Ports 1-4
PSE Communication Connector
TP5
TP4
TP6
TP7
TP3
TP2
100nF
C8
100nF
C10
100nF
C9
100nF
C7
100nF
C6
100nF
C5
100nF
C3
100nF
C4
58V
D1
0.2
R1
GND
PSE_OSS
\PSE_INT
PSE_SDAO
PSE_SDAI
PSE_SCL
\PSE_RST
3.3V
TP8
5016
GNDGND
VPWR
PSE_N1
PSE_N2
PSE_N3
PSE_N4
5
4
1
2
3
6
7
8
9
10
J1
5
4
1
2
3
6
7
8
9
10
J2
GND
VPWR
PSE_N5
PSE_N6
PSE_N7
PSE_N8
TP1
5011
VPWRVPWR
VPWR
PSE_D1
CH1_GATE
CH1_SEN
PSE_D2
CH2_GATE
CH2_SEN
PSE_D5
CH5_GATE
CH5_SEN
PSE_D6
CH6_GATE
CH6_SEN
PSE_D3
CH3_GATE
CH3_SEN
PSE_D4
CH4_GATE
CH4_SEN
PSE_D7
CH7_GATE
CH7_SEN
PSE_D8
CH8_GATE
CH8_SEN
PSE_N8PSE_N7PSE_N4PSE_N3
PSE_N1 PSE_N2 PSE_N5 PSE_N6
0.51
R2
DNP 0.2
R3
0.51
R4
0.51
DNP R9 DNP 0.2
R10
0.51
R11
DNP 0.2
R12
0.2
R5
0.51
R6
DNP 0.2
R7
0.51
R8
0.51
DNP R13 DNP 0.2
R14
0.51
R15
DNP 0.2
R16
58V
D2
58V
D5
58V
D6
58V
D8
58V
D7
58V
D4
VPWR
58V
D3
4 Pair Ports 1-2
4
7,8
1,2, 3
5,6,
Q1
4
7,8
1,2, 3
5,6,
Q2
4
7,8
1,2, 3
5,6,
Q3
4
7,8
1,2, 3
5,6,
Q4
4
7,8
1,2, 3
5,6,
Q7
4
7,8
1,2, 3
5,6,
Q8
4
7,8
1,2, 3
5,6,
Q5
4
7,8
1,2, 3
5,6,
Q6
PSE_D1
PSE_D2
PSE_D3
PSE_D4
PSE_D5
PSE_D6
PSE_D7
PSE_D8
CH1_SEN
CH2_SEN
CH3_SEN
CH4_SEN
CH5_SEN
CH6_SEN
CH7_SEN
CH8_SEN
CH1_GATE
CH2_GATE
CH3_GATE
CH4_GATE
CH5_GATE
CH6_GATE
CH7_GATE
CH8_GATE
\PSE_INT
PSE_SCL
PSE_SDAI
PSE_OSS
PSE_SDAO
\PSE_RST
VPWR
3.3V
GNDGND
0.1µF
C2
0.1uF
C1
GND
12
34
56
78
910
1112
1314
J5
GND
5
4
1
2
3
6
7
8
9
10
11
12
J3
GPIO_1
GPIO_2
GPIO_3
A1-A4 Connector
12
34
56
78
J4
11.0kR22
7.68k
R23
GAT1 1
SEN1
2
DRAIN1
3
KSENSA
4
DRAIN2
5
SEN2
6
GAT2 7
GAT3 8
SEN3
9
DRAIN3
10
KSENSB
11
DRAIN4
12
SEN4
13
GAT4 14
NC 15
NC 16
VPWR
17
NC 18
NC 19
TEST4
20
AGND 21
NC 22
TEST1
23
TEST2
24
TEST3
25
TEST0
26
NC 27
NC 28
GAT5 29
SEN5
30
DRAIN5
31
KSENSC
32
DRAIN6
33
SEN6
34
GAT6 35
GAT7 36
SEN7
37
DRAIN7
38
KSENSD
39
DRAIN8
40
SEN8
41
GAT8 42
VDD
43
RESET
44
INT 45
DGND 46
TEST5
47
A1 48
A2 49
A3 50
A4 51
AUTO 52
SCL
53
SDAI
54
SDAO 55
OSS
56 PAD 57
TPS23881RTQ
U1
124kR17
61.9kR18
35.7kR19
22.6kR20
15.8kR21
1uF
C11
0.01uF
C12
GND
EVM Schematic, Layout Guidelines, PCB Assembly and Layer Plots www.ti.com
20 SLVUBP0A–May 2019–Revised August 2019
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Copyright © 2019, Texas Instruments Incorporated
TPS23881EVM: PoE, PSE, TPS23881 Evaluation Module
Figure 14. TPS23881EVM-008 (Daughterboard) Schematic