ST P-NUCLEO-USB002 User manual

June 2017
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www.st.com
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User manual
STM32 Nucleo pack for USB Type-C™ and Power Delivery with
the Nucleo-F072RB board and the STUSB1602
Introduction
The USB Type-C™ and Power Delivery Nucleo pack P-NUCLEO-USB002 includes:
the NUCLEO-F072RB board
the P-NUCLEO-USB002 expansion board based on the certified STUSB1602 USB Type-C port
controller with PD PHY and BMC driver
a full-featured Type-C cable
These components, together with the X-CUBE-USB-PD certified STM32F0 USB Type-C PD middleware
stack, form a platform for demonstrating USB Type-C and USB Power Delivery (USB PD) capabilities
and facilitating solution development.
The new USB PD protocol expands USB functionality by providing up to 100 W power over the same
cable used for data communication. Devices supporting the protocol are able to negotiate voltage and
current over the USB power pins and define their roles as Provider or Consumer accordingly.
Once the platform is configured, the embedded demonstration firmware can signal cable status
(attached or detached) and orientation information, as well as the role of each of the two ports.
Figure 1: P-NUCLEO-USB002 kit

Contents
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Contents
1USB Type-C and Power Delivery....................................................6
1.1 Overview...........................................................................................6
1.2 Main characteristics ..........................................................................6
1.3 USB Type-C™ pin map.....................................................................7
1.4 Port configurations............................................................................9
1.4.1 Downstream Facing Port (DFP) ......................................................... 9
1.4.2 Upstream Facing Port (UFP).............................................................. 9
1.4.3 Source or provider.............................................................................. 9
1.4.4 Sink or consumer................................................................................ 9
1.4.5 Dual Role Power (DRP)...................................................................... 9
1.5 USB-C PD architecture .....................................................................9
1.5.1 Device Policy Manager (DPM) ......................................................... 10
1.5.2 Policy Engine (PE)............................................................................ 10
1.5.3 Protocol Layer (PRL)........................................................................ 10
1.5.4 Physical layer (PHY)......................................................................... 10
1.6 CC pins: port termination characteristics.........................................11
1.7 Power options .................................................................................11
1.8 Cable attachment and detachment detection and orientation .........12
1.9 Power negotiation ...........................................................................13
1.10 Full-featured Type-C™ cable and VCONN supply .............................14
1.11 Alternate modes and billboard device class....................................15
2System architecture......................................................................17
2.1System block scheme .....................................................................19
2.2 NUCLEO-F072RB STM32 Nucleo board........................................19
2.3 P-NUCLEO-USB002 expansion board............................................21
2.3.1 P-NUCLEO-USB002 expansion board: USB Type-C connectors,
voltage and current sense stage...................................................................... 24
2.3.2 P-NUCLEO-USB002 expansion board: STUSB1602 USB Type-C
controller 26
2.3.3 P-NUCLEO-USB002 expansion board: VCONN switch...................... 28
2.3.4 P-NUCLEO-USB002 expansion board: VBUS management........... 30
2.3.5 P-NUCLEO-USB002 expansion board: local power management
stage 31
2.3.6 P-NUCLEO-USB002 expansion board: STSAFE secure device..... 32
2.3.7 P-NUCLEO-USB002 expansion board: USB2.0.............................. 33
2.3.8 P-NUCLEO-USB002 expansion board: ESD protections ................ 34

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2.3.9 P-NUCLEO-USB002 expansion board: connectors......................... 35
2.3.10 P-NUCLEO-USB002 expansion board: test points.......................... 37
2.3.11 P-NUCLEO-USB002 expansion board: jumpers.............................. 38
2.3.12 P-NUCLEO-USB002 expansion board: user LEDs.......................... 38
2.4 Full-featured Type-C cable..............................................................38
3System setup.................................................................................39
3.1 Source power role configuration......................................................39
3.1.1 Using the NUCLEO-F072 on-board voltage regulator ..................... 39
3.1.2 Using an external power supply ....................................................... 39
3.2 Sink power role configuration..........................................................40
3.2.1 Using the NUCLEO-F072RB on-board voltage regulator ................ 40
3.2.2 Using an external provider ............................................................... 40
3.3 Dual Role Power configuration........................................................41
3.3.1 Using the NUCLEO-F072RB on-board voltage regulator ................ 41
3.3.2 Using an external power supply ....................................................... 41
4Ordering information.....................................................................42
5Electrical schematics....................................................................43
6Bill of materials..............................................................................48
7Acronyms and abbreviations .......................................................52
8References.....................................................................................53
9Revision history ............................................................................54

List of tables
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List of tables
Table 1: USB Type-C pinout description ....................................................................................................8
Table 2: Source CC termination (Rp) requirements .................................................................................11
Table 3: Sink CC termination (Rd) requirements......................................................................................11
Table 4: Power options.............................................................................................................................12
Table 5: NUCLEO-F072RB solder bridges and resistors to be modified .................................................20
Table 6: P-NUCLEO-USB002 expansion board VCONN settings ...........................................................28
Table 7: P-NUCLEO-USB002 expansion board JP100 and JP101 settings............................................33
Table 8: P-NUCLEO-USB002 expansion board serial communication connection .................................36
Table 9: P-NUCLEO-USB002 expansion board test points .....................................................................37
Table 10: P-NUCLEO-USB002 expansion board jumpers.......................................................................38
Table 11: P-NUCLEO-USB002 expansion board LED signaling .............................................................38
Table 12: List of acronyms........................................................................................................................52
Table 13: Document revision history ........................................................................................................54

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List of figures
Figure 1: P-NUCLEO-USB002 kit...............................................................................................................1
Figure 2: USB plug form factors .................................................................................................................7
Figure 3: USB Type-C plug pinout..............................................................................................................7
Figure 4: USB Type-C receptacle pinout....................................................................................................8
Figure 5: USB power delivery architecture...............................................................................................10
Figure 6: Pull up/down CC detection ........................................................................................................12
Figure 7: Message flow during power negotiation....................................................................................14
Figure 8: Pins available for reconfiguration on the plug of the full-featured cable ...................................15
Figure 9: Pins available for reconfiguration on the receptacle for direct connect applications.................15
Figure 10: The two boards composing the P-NUCLEO-USB002 kit ........................................................17
Figure 11: Block scheme of the complete architecture.............................................................................19
Figure 12: STM32 Nucleo development board.........................................................................................20
Figure 13: STM32 Nucleo board top and bottom view .............................................................................21
Figure 14: P-NUCLEO-USB002 expansion board....................................................................................22
Figure 15: P-NUCLEO-USB002 expansion board functional blocks........................................................22
Figure 16: P-NUCLEO-USB002 expansion board connectors and jumpers............................................23
Figure 17: P-NUCLEO-USB002 expansion board silkscreen...................................................................23
Figure 18: P-NUCLEO-USB002 expansion board USB Type-C receptacle and current sensing (port 0)
schematic view..........................................................................................................................................24
Figure 19: P-NUCLEO-USB002 expansion board USB Type-C receptacle and Current sensing (port 1)
schematic view..........................................................................................................................................25
Figure 20: P-NUCLEO-USB002 expansion board Port 0 Current sensing stage schematic view...........25
Figure 21: P-NUCLEO-USB002 expansion board Port 1 Current sensing stage schematic view...........26
Figure 22: STUSB1602 front end for Port 0 .............................................................................................27
Figure 23: P-NUCLEO-USB002 expansion board: JP000 and JP001 jumper settings to provide VCONN
through the local voltage regulator ...........................................................................................................29
Figure 24: P-NUCLEO-USB002 expansion board Port 0 schematic view of the VBUS management
mechanism................................................................................................................................................30
Figure 25: P-NUCLEO-USB002 expansion board Port 1 schematic view of the VBUS management
mechanism................................................................................................................................................30
Figure 26: P-NUCLEO-USB002 expansion board: schematic view of the load switches of the local
power management..................................................................................................................................31
Figure 27: P-NUCLEO-USB002 expansion board: schematic view of the local DC-DC converter..........32
Figure 28: P-NUCLEO-USB002 expansion board: STSAFE-A100 schematic view ................................32
Figure 29: P-NUCLEO-USB002 expansion board: JP100 and JP101 connectors for USB 2.0
configurations............................................................................................................................................34
Figure 30: P-NUCLEO-USB002: CN13 and C14 connector pinout..........................................................35
Figure 31: P-NUCLEO-USB002: CN4 connector .....................................................................................36
Figure 32: P-NUCLEO-USB002 expansion board CN2_1 and CN3_TX pin indications .........................37
Figure 33: P-NUCLEO-USB002 mounting orientation..............................................................................39
Figure 34: P-NUCLEO-USB002 expansion board circuit schematic - global view...................................43
Figure 35: P-NUCLEO-USB002 expansion board circuit schematic - MCU interface .............................43
Figure 36: P-NUCLEO-USB002 expansion board circuit schematic - STUSB1602 front end Port0 .......44
Figure 37: P-NUCLEO-USB002 expansion board circuit schematic - STUSB1602 front end Port1 .......44
Figure 38: P-NUCLEO-USB002 expansion board circuit schematic - local power ..................................45
Figure 39: P-NUCLEO-USB002 expansion board circuit schematic - local voltage supply.....................45
Figure 40: P-NUCLEO-USB002 expansion board circuit schematic - Type-C Connector 0....................46
Figure 41: P-NUCLEO-USB002 expansion board circuit schematic - Type-C Connector 1....................46
Figure 42: P-NUCLEO-USB002 expansion board circuit schematic - Current Sensing C0.....................47
Figure 43: P-NUCLEO-USB002 expansion board circuit schematic - Current Sensing C1.....................47
Figure 44: P-NUCLEO-USB002 expansion board circuit schematic - security........................................47

USB Type-C and Power Delivery
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1 USB Type-C and Power Delivery
1.1 Overview
The USB Type-C™ and Power Delivery technologies simplify development and enhance
user experience; the new reversible USB Type-C connector insertion is more intelligent and
user friendly.
These technologies offer a smart connector able to carry all the necessary data (including
video) as well as negotiate up to 100 W supply or charge connected equipment according
to the Power Delivery protocol.
Less cables, less connectors and universal chargers are among the final objectives.
The USB Type-C connector supports up to 15 W (5 V at 3 A), which rises to 100 W (up to
20 V at 5 A) adopting the USB Power Delivery feature.
1.2 Main characteristics
The USB Implementer Forum (USB-IF) introduces these complementary specifications:
1. the USB Type-C™ receptacle, plug and cable specification rev. 1.2
2. the USB Power Delivery (PD) specification rev. 2.0 that allows two PD compliant
entities to exchange up to 100 W during their negotiations.
Any system embedding a USB Type-C receptacle or plug which is designed to implement a
USB Power Delivery application such as a single port device, a multi-port hub or a simple
cable is based on these specifications.
The connector is intended for a wide range of charging applications like computers,
displays and mobile phones, with all the advanced features of PD:
power role negotiation
power sourcing and consumption level negotiation
electronically marked cable identification
vendor-specific message exchange
alternate-mode negotiation, allowing different communication protocols to be routed
onto the reconfigurable pins of the USB Type-C connectors.
The cables use the same male connector on both ends.

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Figure 2: USB plug form factors
The new USB Type-C covers all the features provided by the previous generation USB
plugs in a single connector, rendering USB usage easier and more flexible. It supports all
protocols from USB2.0 onward, including power capability.
The USB Type-C connection allows ports to operate in host-mode only, device-mode only
or dual-role. Both data and power roles can be independently and dynamically swapped
using the USB PD protocol.
1.3 USB Type-C™ pin map
USB Type-C™ plugs and receptacles are 24-pin connectors with two groups of pin
connections arranged so as to ensure pinout reversibility for any connection.
The symmetrical connections: are
eight power pins: VBUS/GND
USB2.0 differential pairs (D+/D-)
The asymmetrical connections are:
two sets of Tx/Rx signal paths supporting USB3.1 data rates
two configuration channels (CC lines) for the discovery, configuration and
management of USB Type-C power delivery features
two sideband use (SBU lines) signals for analog audio modes; may be used by
alternate mode.
Figure 3: USB Type-C plug pinout

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Figure 4: USB Type-C receptacle pinout
Table 1: USB Type-C pinout description
Pin
Receptacle
signal
Plug
signal
Description
Comment
A1
GND
GND
Ground return
Can be up to 5 A split into
four pins
A2
TX1+
TX1+
USB3.1 data lines or Alternate
10-Gbyte TX differential
pair in USB 3.1
A3
TX1-
TX1-
A4
VBUS
VBUS
Bus power
Max power is 100 W (20 V
at 5 A) split into four pins
A5
CC1 or VCONN
CC
Configuration channel or power for
active or electronically marked
cable
In VCONN configuration,
max. power is 1 W
A6
D+
D+
USB2.0 datalines
-
A7
D-
D-
-
A8
SBU1
SBU1
Sideband Use (SBU)
Alternate mode only
A9
VBUS
VBUS
Bus power
Max power is 100 W split
into four pins
A10
RX2-
RX2-
USB3.1 datalines or Alternate
10-Gbyte RX differential
pair in USB 3.1
A11
RX2+
RX2+
A12
GND
GND
Ground return
Can be up to 5 A split into
four pins
B1
GND
GND
Ground return
Can be up to 5 A split into
four pins
B2
TX2+
TX2+
USB3.1 datalines or Alternate
10-Gbyte RX differential
pair in USB 3.1
B3
TX2-
TX2-
B4
VBUS
VBUS
Bus power
Max power is 100 W split
into four pins
B5
CC2 or VCONN
VCONN
Configuration channel or power for
active or electronically marked
cable
In VCONN configuration,
max. power is 1 W
B6
D+
-
USB2.0 datalines
-
B7
D-
-
-
B8
SBU2
SBU2
Sideband Use (SBU)
Alternate mode only
B9
VBUS
VBUS
Bus power
Max power is 100 W split
into four pins

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Pin
Receptacle
signal
Plug
signal
Description
Comment
B10
RX1-
RX1-
USB3.1 datalines or Alternate
10-Gbyte RX differential
pair in USB 3.1
B11
RX1+
RX1+
B12
GND
GND
Ground return
Can be up to 5 A split into
four pins
1.4 Port configurations
As stated in the USB Type-C™ and USB Power Delivery specifications, a data role (host or
device) and a power role (source, sink or DRP) can be assigned to each port. Both data
and power roles can be independently and dynamically swapped according to rules and
procedures established by the specifications.
1.4.1 Downstream Facing Port (DFP)
The downstream facing port is associated with the flow of data in a USB connection. It is
usually the port on a host or hub which devices connect to.
In its initial state, the DFP must be able to supply VBUS and VCONN and support data.
1.4.2 Upstream Facing Port (UFP)
The upstream facing port is associated with the data flow in a USB connection. It
represents the port on a device or a hub that connects to a host or the DFP of a hub. In its
initial state, UFP sinks VBUS and supports data (e.g., display).
1.4.3 Source or provider
This port must source power over VBUS (5 V to 20 V and up to 5 A), and most commonly
belongs to a host or hub DFP. A provider must assert an Rp resistor (pull-up resistor, See
Figure 5: "USB power delivery architecture") on CC pins (configuration channel pins, see
Section 1.6: "CC pins: port termination characteristics").
1.4.4 Sink or consumer
This port is able to sink power over VBUS, making use of power (from 5 V to 20 V and up to
5 A), most commonly embedded on a device or UFP. A Consumer must assert an Rd
resistor (pull-down resistor: see Figure 5: "USB power delivery architecture") on CC pins.
1.4.5 Dual Role Power (DRP)
A dual role power USB port can operate as a source or a sink. The initial role of the port
may be fixed or may alternate between the two port states.
Initially, when operating as a source, the port also assumes the role of DFP; when
operating as a sink, the port takes the role of UFP.
The port role may be changed dynamically to reverse power.
1.5 USB-C PD architecture
The USB Power Delivery specification defines the stack architecture with all its layers
managing a PD device.

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Figure 5: USB power delivery architecture
As per the USB Power Delivery protocol, a USB DFP is initially a Source and a USB UFP is
initially a Sink. When these two entities are connected between them, they start to
communicate by means of the configuration channel (CC), while the Source supplies the
Sink through the VBUS path. Although USB-PD enables the Source/Sink and the DFP/UFP,
the roles may be swapped every time the application requests it.
1.5.1 Device Policy Manager (DPM)
The device policy manager deals with the USB Power Delivery resources used by one or
more ports on the basis of the local device policy. It interacts with the policy engines and
cable detection entities of the device to implement the local policies for each port.
1.5.2 Policy Engine (PE)
The policy engine interacts directly with the DPM to determine which local policy to apply.
Its role is to drive the message sequences according to the sent message and its expected
response.
It allows power negotiation by establishing an explicit contract for power exchange. The
acceptance or the refusal of a request depends on the response of the DPM with respect to
a specific power profile.
The PE also handles the flow of vendor defined messages, allowing the discovery, entry
and exit of modes supported by the provider and consumer sides.
1.5.3 Protocol Layer (PRL)
The protocol layer drives message construction, transmission, reception and
acknowledgment. It allows the monitoring of message flows and the detection of
communication errors.
1.5.4 Physical layer (PHY)
The physical layer is responsible for sending and receiving messages across the CC wire.
It consists of a transceiver that superimposes a BMC signal on the wire. It is responsible for
managing data over the wire, avoiding collisions and detecting errors in the messages
using a Cyclic Redundancy Check (CRC).

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1.6 CC pins: port termination characteristics
The configuration channel (CC) pins are used in the discovery, configuration and
management of connection across a USB Type-C™ cable, as well as a communication
channel for the PHY layer of the USB Power Delivery.
There are two CC pins in each receptacle, but only one is connected through the cable to
establish communication. The other pin can be re-assigned as the VCONN pin for powering
electronics in the USB Type-C™ plug of electronically-marked cables.
Specific Rd and Rp resistor values connected to CC pins allow single role or dual role
system configuration. The attachment and orientation detection operations are carried out
through CC lines through these resistors:
a source must assert Rp pull-up resistors on both CC1 and CC2
a sink must assert Rd pull-down resistors on both CC pins
a dual role power (DRP) is equipped with both Rp pull-up resistors and Rd pull-down
resistors on its CC pins and is able to dynamically assert the appropriate resistors
when the role is fixed by the application according to the operated power role.
A full-featured USB Type-C cable must assert Ra pull-down resistors on the VCONN pin.
The following table provides the values to be used for Rp or current source.
Table 2: Source CC termination (Rp) requirements
Source
Current Capability
Current Source
to 1.7 V - 5.5 V
Rp pull-up
to 3.3 V ±5%
Rp pull-up
to 4.75 V - 5.5 V
Default USB power
80 µA ±20%
36 kΩ ±20%
56 kΩ ±20%
1.5 A at 5 V
180 µA ±8%
12 kΩ ±5%
22 kΩ ±5%
3.0 A at 5 V
330 µA ±8%
4.7 kΩ ±5%
10 kΩ ±5%
Rp resistors connected to both CC pins may be pulled-up to 3.3 V or 5 V. The resistor
value is chosen on the basis the device port supplying capability. Moreover, if the source
role is operated, the Rp resistors can be replaced by current sources.
The following table provides the values to be used for Rd or Sink CC termination.
Table 3: Sink CC termination (Rd) requirements
Rd setting
Nominal Value
Max Voltage on pin
Power Capability detection
±20% voltage clamp
1.1 V
1.32 V
No
±20% resistor to GND
5.1 kΩ
2.18 V
No
±10% resistor to GND
5.1 kΩ
2.04 V
Yes
Rd resistors may be implemented in multiple ways.
1.7 Power options
Regarding power exchange, every platform equipped with a Type-C™ connector but
without power delivery must be able to support 5 V with one of the specific current
capabilities. When power delivery is supported and the design is specifically optimized for
managing high power loads, the same platform may support up to 20 V at 5 A (100 W).

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Table 4: Power options
Mode of operation
Nominal
voltage
Maximum
current
Maximum
power
Note
USB 2.0
5 V
500 mA
2.5 W
Default current based on
specification
USB 3.1
900 mA
4.5 W
USB BC1.2
up to 1.5 A
7.5 W
Legacy charging
USB Type-C™
current at 1.5 A
1.5 A
Support high power devices
USB Type-C™
current at 3 A
3 A
15 W
USB PD
up to 20 V
up to 5 A
100 W
Directional control and power
level management
1.8 Cable attachment and detachment detection and orientation
As stated in the USB Power Delivery specification, it is mandatory to determine the
orientation of an attachment; i.e., when one of the two CC pins detects a valid Rp/Rd
connection.
To detect an attachment, the source monitors both CC pins.
The pins are floating when nothing is attached, but when the sink is attached via the cable,
one CC line of the source is directly pulled-down (through the sink Rd), signalling that a
connection has been made (see Figure 6: "Pull up/down CC detection").
Hence, once connection is established, a voltage divider is set between source pull-up
resistor Rp and sink pull-down resistor Rd, fixing the voltage level on the CC line for the
communication signals.
Figure 6: Pull up/down CC detection
At the same time, the orientation of the plug, and consequently of the cable, is defined
according to which CC line (CC1 or CC2) detects a valid resistance after the attach event.
The figure above shows an unflipped cable orientation.
Moreover, the full-featured cable, exposing an Ra resistor, connects the VCONN pins to
ground.

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1.9 Power negotiation
When a connection is made and the respective roles have been assigned, the source and
the sink negotiate a contract for the power objects: the selected configuration channel (CC)
allows them to establish communication and negotiate the power according to the protocol
described in USB Power Delivery specification.
Originally, all the devices equipped with USB Type-C™ are able to provide up to 15 W (5 V
and up to 3 A) power via the VBUS path, but every subsequent request for delivering or
receiving power from 15 W to 100 W (5 V at 3 A to 20 V at 5 A) must be negotiated
according to the USB Power Delivery protocol.
The messages exchanged between a source (provider) and sink (consumer) are illustrated
in Figure 7: "Message flow during power negotiation".
1. Initially, the source dispatches a Source_Capabilities message to inform the port
partner (sink) of its power capabilities.
2. The sink then sends a Request for one of the advertised power profiles.
3. The source accepts or rejects this request according to its power balance.
4. If confirmed, the source sends an Accept to the sink
5. The source then switches to the requested power profile and sends a PS_Ready
confirmation message.
Each received message is acknowledged with a GoodCRC to confirm correct reception.
Incorrect reception should be ignored and persistent communication errors should trigger a
soft reset to reset protocol parameters and re-establish communication. If the error
persists, a hard reset is performed.

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Figure 7: Message flow during power negotiation
1.10 Full-featured Type-C™ cable and VCONN supply
Full-featured Type-C™ cables are Type-C™ to Type-C™ cables that support USB2.0 and
USB3.1 data operation, and include sideband use (SBU) wires.
All USB full-featured Type-C cables must be electronically marked and must provide 800 Ω
to 1.2 kΩ impedance (Ra) that connects the assigned VCONN pin to ground.
When a full-featured cable is attached to a source, the source must provide a VCONN (5 V
default) to supply it (valid voltage range is 3 V to 5.5 V).
Up to 1 W may be drawn from VCONN to power the ICs in the plug, necessary to implement
electronically-marked cables and VCONN-powered accessories.

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The VCONN is systematically assigned to the free CC pin of the receptacle after a connection
is established: the CC pins can be monitored to verify a valid Rp/Ra connection and then
the VCONN supply is routed by the source to the checked pin.
Since all the full-featured Type-C™ cables are reversible, both CC pins in the receptacle
must be able to assume the role of CC and VCONN on cable insertion.
1.11 Alternate modes and billboard device class
The USB Power Delivery specification supports alternate mode (Alt Mode) to transfer high-
speed data over Type-C™ cables using protocols like:
High-Definition Multimedia Interface (HDMI)
DisplayPort (DP)
Peripheral Component Interconnect Express (PCI Express)
Ethernet over twisted pair (Base-T Ethernet)
Mobile High-Definition Link (MHL)
The adoption of alternate mode lets Type-C hosts and devices incorporate additional
functionality, exploiting USB PD structured vendor defined messages (Structured VDMs) to
manage typical display controller selection mechanisms: discover, enter and exit.
As alternate modes do not traverse the USB hub topology, they may only be used between
a directly connected host and device.
Structured VDMs may also be used for re-assignment of the pins that the USB Type-C
connector exposes.
Figure 8: Pins available for reconfiguration on the plug of the full-featured cable
The following figure shows the pins available for reconfiguration with direct connect
applications. There are three more pins because this configuration is not limited by the
cable wiring.
Figure 9: Pins available for reconfiguration on the receptacle for direct connect applications
Where no equivalent USB functionality is implemented, the device must provide a USB
interface exposing a USB billboard device class to identify the device. This is not required
for non-user facing modes (e.g., diagnostic modes).

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The USB billboard device class definition describes how to communicate the alternate
modes supported by a device container to a host system, including string descriptors that
provide supporting information in a human-readable format.

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2 System architecture
The P-NUCLEO-USB002 USB Type-C™ and power delivery kit includes:
1. a NUCLEO-F072RB development board acting as the control board running the stack
2. a P-NUCLEO-USB002 expansion board acting as a Type-C and Power Delivery
interface, with two STUSB1602 Type-C PD controllers
3. A full-featured and certified USB Type-C cable
Figure 10: The two boards composing the P-NUCLEO-USB002 kit
The P-NUCLEO-USB002 USB Type-C and Power Delivery expansion board is equipped
with:
two DRP USB Type-C™ ports managed by two STUSB1602 Type-C port controllers
optional VBUS current sensing (and discrete voltage monitoring)
dedicated power connector to interface with an external power supply (not included) to
provide different profiles as well as VCONN (5V), if necessary
on-board power management able to provide internal supply voltages
six status-control LEDs for USB-PD port purposes, a user LED and a power LED
USB 2.0 interface capability available on both Type-C portsthere is only one USB 2.0
controller, which can be mapped to either port or in pass-through configuration.
RoHS compliant
PCB type and size:
PCB material: FR4
four-layer architecture
copper thickness: 35 µm
The NUCLEO-F072RB board includes:

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an STM32F072RBT6 32-bit microcontroller based on ARM®Cortex®-M0 with 128-
Kbytes of Flash memory, 16-Kbytes of SRAM and a USB 2.0 full speed data interface
in a LQFP64 package
extension resources:
Arduino Uno revision 3 connectivity
ST morpho extension pin headers for full access to all STM32 I/Os
on-board ST-LINK/V2-1 debugger/programmer with SWD connector:
selection-mode switch to use the kit as a standalone ST-LINK/V2-1
flexible board power supply:
USB VBUS on Type-B connector or external source
Power management access point
LEDs:
USB communication (LD1)
user LED (LD2)
power LED (LD3)
push buttons:
USER
RESET
USB re-enumeration capability; interfaces supported on USB:
Virtual Com port
Mass storage
Debug port
Supported by various integrated development environments (IDEs):
IAR™
Keil®
GCC-based IDEs
The NUCLEO-F072RB included in the kit has a different solder bridge
configuration with respect to the default one (see Table 5: "NUCLEO-F072RB
solder bridges and resistors to be modified")

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2.1 System block scheme
Figure 11: Block scheme of the complete architecture
2.2 NUCLEO-F072RB STM32 Nucleo board
The STM32 Nucleo board provides an affordable and flexible way for solution and
prototype development with any of STM32 microcontroller lines.
The board STM32F072RBT6 32-bit microcontroller is based on the ARM®Cortex®-M0 with
128 Kb Flash memory and 16 Kb SRAM.
The Arduino™ connectivity support and ST morpho headers make it easy to expand with a
wide range of specialized expansion boards.
Separate probes are not required as it integrates the ST-LINK/V2-1 debugger/programmer.
The STM32 Nucleo board comes with the comprehensive STM32 HAL software library
together with various packaged software examples.
Visit http://www.st.com/stm32nucleo for more information.

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Figure 12: STM32 Nucleo development board
The solder bridge configuration on the NUCLEO-F072RB Nucleo board is customized to
support USB PD applications (see Table 5: "NUCLEO-F072RB solder bridges and resistors
to be modified" and Figure 13: "STM32 Nucleo board top and bottom view").
For further information, please refer to user manual UM1724 STM32 Nucleo-64 boards on
www.st.com.
Table 5: NUCLEO-F072RB solder bridges and resistors to be modified
Bridge
reference
State
Description
SB13
OFF
PA2 and PA3 on STM32F103CBT6 (ST-LINK MCU) are disconnected from
PA3 and PA2 of the STM32F072RBT6 MCU.
SB14
SB15
OFF
The SWO signal is not connected to PB3 on STM32F072RBT6 MCU.
SB21
OFF
Green user LED LD2 is not connected to PA5 on STM32F072RBT6 MCU.
R34
OFF
LSE not used: PC14 and PC15 used as GPIOs instead of low speed clock.
R36
SB48
ON
SB49
SB62
ON
To connect another USART (not the default USART2) to STLINK MCU,
using flying wires between ST morpho connector and CN3.
SB13 and SB14 should be OFF.
SB63