ST X-NUCLEO-SRC1M1 User manual

Introduction
The X-NUCLEO-SRC1M1 expansion board allows evaluating the features of TCPP02-M18 for the USB Type-C™ and the
protections for VBUS and CC lines suitable for source applications.
The expansion board is designed to be stacked on top of any STM32 Nucleo-64 development board with Power Delivery
(UCPD) peripheral embedded in their microcontrollers.
You can also stack it on top of any other STM32 Nucleo-64 development board not supporting the UCPD peripheral for 5
V, source only, to demonstrate the USB Type-C™ basic operations (attach, detach and 5 V power supply current capability
information).
When using an STM32 Nucleo-64 development board with Power Delivery peripheral, data functionalities as a host device or
dual role data (DRD) are also allowed.
The X-NUCLEO-SRC1M1 provides an effective demonstration of the source operation of the USB Type-C™ connector when
an external compatible source is connected to the board. The integrated ST715PU33R LDO linear regulator can supply the
connected STM32 Nucleo development board.
The X-NUCLEO-SRC1M1 is compliant with the latest USB Type-C™ and Power Delivery specifications.
The companion software package (X-CUBE-TCPP) contains the application examples for the development boards embedding
UCPD-based microcontrollers (for example, NUCLEO-G071RB, NUCLEO-G474RE, and NUCLEO-G0B1RE) and for those not
supporting the UCPD peripheral (NUCLEO-L412RB-P).
Figure 1. X-NUCLEO-SRC1M1 expansion board
Getting started with the X-NUCLEO-SRC1M1 USB Type-C™ Power Delivery
source expansion board based on TCPP02-M18 for STM32 Nucleo
UM2973
User manual
UM2973 - Rev 1 - December 2021
For further information contact your local STMicroelectronics sales office. www.st.com

1Getting started
1.1 Overview
The X-NUCLEO-SRC1M1 expansion board features:
• Supports all USB Type-C™ Power Delivery SPR profiles up to 100 W
• Manage source role data/power configuration
• Compliant with USB 2.0 dual role data according to STM32 USB data capability
• 8/20 μs surges and overcurrent protections, and discharge for VBUS
• Short to VBUS protection for configuration channel pins (CC1 and CC2)
• ESD protection (IEC61000-4-2 level 4 ± 8 kV contact discharge) for CC1, CC2, D+, and D-
• Overvoltage and overcurrent protections, and discharge for VCONN
• Common mode filter on D+/D- data lines
• Two power modes to optimize the current consumption
• Compliant with programmable power supplies (PPS)
• Free comprehensive development firmware library
• Compliant with STM32 Nucleo-64 boards featuring an STM32 with UCPD feature for Power Delivery and
without UCPD feature for a 5 V solution only
The X-NUCLEO-SRC1M1 provides an interface among three major blocks for the USB Type-C™ Power Delivery
source:
• USB Type-C™ connector;
• the Power Delivery controller embedded in the STM32 (UCPD) on the STM32 Nucleo development board;
• the power supply.
It also provides USB 2.0 data lines interface connection to the STM32 Nucleo MCU.
The BoM is optimized without compromising the protections for:
• VBUS line: overcurrent and surge protections;
• CC lines: overvoltage, overcurrent, and ESD protections;
• data lines: ESD protection and EMI filtering.
As required by the Power Delivery protocol, the TCPP02-M18 features:
• CC lines switch matrix for VCONN;
• VBUS discharge;
• VCONN discharge.
Fault mode report and two optimized power modes are also available.
All these features are managed through I²C communication.
The VBUS current analog readout is also possible when the STM32 ADC is connected to the TCPP02-M18
differential amplifier output.
The following hardware configurations are possible depending on the STM32 UCPD peripheral:
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• the STM32 embeds the UCDP peripheral: 5 V to 20 V PD source or PPS source can be connected to the
provider path
Figure 2. Block diagram of X-NUCLEO-SRC1M1 connected to the STM32 Nucleo with UCPD
Firmware
I2C
USB Type-C™
VBUS
Provider path N-MOSFET
Configuration channels
USB 2.0 Data lines
Protections
STM32 Nucleo development board
ADC
X-NUCLEO-SRC1M1 expansion board
TCPP02-M18
UCPD
STM32
connector
Power bus
CC1/CC2 lines
D+/D-lines
USB 2.0
• the STM32 does not embed the UCPD peripheral: 5 V source only can be connected to the provider path
Figure 3. Block diagram of X-NUCLEO-SRC1M1 connected to the STM32 Nucleo without UCPD
STM32
Firmware
I2C
USB Type-C™
BUS
Power bus
Provider path N-MOSFET
Configuration channels
USB 2.0 Data lines
Protections
STM32 Nucleo development board
ADC
X-NUCLEO-SRC1M1 expansion board
TCPP02-M18
connector
V
CC1/CC2 lines
D+/D- lines
Note: In both the figures above, the solid lines indicate the USB Type-C™ connector connections, whereas the dotted
lines indicate internal connections.
1.2 Hardware architecture
The X-NUCLEO-SRC1M1 expansion board can be used with any STM32 Nucleo-64 development board.
The expansion board must be plugged on the matching pins of the development board CN7 and CN10 ST
morpho connectors.
Two hardware configurations are possible depending on the STM32 UCPD peripheral:
• if the STM32 embeds a UCDP peripheral, connect JP2 and JP3 jumpers to CC1_UCPD and CC2_UCPD,
respectively;
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• if the STM32 does not embed a UCPD peripheral, connect JP2 and JP3 jumpers to CC1_noUCPD and
CC2_noUCPD, respectively.
When plugged onto an STM32 Nucleo development board, the expansion board can be supplied in two different
ways:
• through the STM32 Nucleo ST-LINK supply by using the development board internal LDO;
• through the CN3 screw connector and thanks to the integrated ST715PU33R LDO linear regulator (U2) that
supplies the entire system.
Figure 4. X-NUCLEO-SRC1M1 main functional blocks (top view)
1 and 2: Morpho connectors
3, 4, 5, and 6: Arduino connectors
7: USB Type-C™ connector (CN1)
8: Provider path screw connector (CN3) + LED
9: Jumpers for CC lines configuration (JP2 and JP3)
10: 3.3 V LED
11: Jumpers for the board self-power (LDO out + NRST)
12: TCPP02-M18 USB Type-C™ source protection
13: ECMF02-2AMX6 common mode filter + ESD protection
14: ESDA25P35-1U1M TVS diode
12
3
4
5
6
7
8
9
11
12
14
10
13
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Figure 5. X-NUCLEO-SRC1M1 main functional blocks (bottom view)
1 and 2: Morpho connectors
3, 4, 5, and 6: Arduino connectors
7: 5 V only current capability table
8: STL40DN3LLH5 automotive-grade dual N-channel 30 V, 0.016 mΩ, 11 A STripFET H5 power MOSFET
9: Current sense 7 mΩ shunt resistor
10: ST715PU33R high input voltage LDO linear voltage regulator
2
3
4
5
6
7
8
9
10
1
1.2.1 USB Type-C™ connector
The USB Type-C™ receptacle (CN1) gathers the VBUS path and the main connections, such as CC lines and
USB 2.0 data lines (DP, DM), before dispatching data to the major functional blocks.
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Figure 6. USB Type-C™ receptacle (CN1) and ESDA25P35-1U1M TVS diode (D1)
C13
2.2uF 50V
GND
D1
ESDA25P35-1U1M
TP2
SH22
VBUS
GND
GND
TP5
TP3
C1
330pF 50V
CN1
ConUSB31_632723300011_recept
CC1
A5
Dn1
A7
Dp1
A6
GND1
GND1
GND2
GND2
GND3
A1
GND5
A12
GND6
B12
SBU1
A8
SHELL1
SHELL1
SHELL2
SHELL2
SHELL3
SHELL3
SHELL4
SHELL4
SHELL5
SHELL5
SHELL6
SHELL6
SSRXn1
B10
SSRXn2
A10
SSRXp1
B11
SSRXp2
A11
SSTXn1
A3
SSTXp1
A2
VBUS1
A4
VBUS2
A9
VBUS4
B9
Dn2
B7
Dp2
B6
GND4
B1
SBU2
B8
SSTXn2
B3
SSTXp2
B2
VBUS3
B4
CC2
B5
TP4
C2
330pF 50V
TP1
CC1c
CC2c
An ESDA25P35-1U1M TVS diode (D1) protects the VBUS power line and, consequently, the entire system against
electrical overstress (EOS) when you connect a sink through the USB Type-C™ cable.
To be compliant with the USB Power Delivery standard requirements, the board embeds the 330 pF C1 and C2
capacitors, as well as the 2.2 µF C13 capacitor, which ensures a good system robustness.
1.2.2 USB 2.0 data path and configuration settings
The X-NUCLEO-SRC1M1 expansion board allows the STM32 Nucleo development boards that feature a USB 2.0
peripheral to expose the D+/D- lines on the USB Type-C™ receptacle (CN1).
Most STM32 Nucleo-64 development boards feature this functionality on the CN10-12 and CN10-14 pins of
the ST morpho connectors. The NUCLEO-L412RB-P, NUCLEO-L433RC-P, NUCLEO-L452RE-P and NUCLEO-
L476RG development boards, instead, map USB 2.0 data on CN10-33 and CN10-17 pins.
Two couples of resistances are connected to the ECMF02-2AMX6 (U3) USB 2.0 data line protection to extend the
use of this peripheral to all the STM32 Nucleo-64 development boards.
Figure 7. USB2.0 data line protection ECMF02-2AMX6 (U3) and resistor setup
GND
DP_G4
DP_XX
DM_G4
CC1_G4
ESD
ESD ESD
ESD
D-
GND
D-
D+D+
NC
R19 0
SH13
SH11
R20 0
SH22
D+ecmf
D-ecmf
90 ohms
ZDiff 90 ohms
ZDiff
ECMF02-2AMX6
U3
DM_xx
DP_xx
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By default, the X-NUCLEO-SRC1M1 expansion board mounts R19 and R20 resistors fitted to guarantee USB
2.0 compatibility with all the main microcontroller families. However, for the L4 family (NUCLEO-L412RB-P,
NUCLEO-L433RC-P, NUCLEO-L452RE-P, and NUCLEO-L476RG), you have to remove and replace them with
SH11 and SH13 solder bridges.
D+/- lines are used as data lines (the SH22 solder bridge is opened by default). Short them for source only by
closing the SH22 solder bridge except for 5 V, 0.5 A source in order to ensure compatibility with the USB BC 1.2
standard.
1.2.3 ST morpho and Arduino UNO V3 connectors
The figure below shows the ST morpho and Arduino UNO V3 connectors of the X-NUCLEO-SRC1M1 expansion
board. It details the main connections, functions, and configuration settings.
Figure 8. ST morpho and Arduino UNO V3 connectors
3.3V
GND
GND
GND
5 V
I2C1_SCL
I2C1_SDA
NRST CC1_G4 DP_G4
DM_G4
ADC_Vbusc
ADC_Prov
CC1_G0
ADC_Isense
DP_XX
CC1
CC2
CC1-5V
CC2-5V
ENABLE
FLGN
CN5
SSQ-110-03-F-S
1
2
3
4
5
6
7
8
9
10
CN6
SSQ-108-03-F-S
1
2
3
4
5
6
7
8
R26 0
R31
0
CN10
ESQ-119-14-T-D
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38
1
3
5
7
9
11
13
15
17
19
21
23
25
27
29
31
33
35
37
R27 0
R41
100
JP2
JUMPER_3PIN
1
2
3
CN7
ESQ-119-14-T-D
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38
1
3
5
7
9
11
13
15
17
19
21
23
25
27
29
31
33
35
37
CN9
SSQ-108-03-F-S
1
2
3
4
5
6
7
8
R24 0
R25 0
R40
100
JP3
JUMPER_3PIN
1
2
3
CN8
SSQ-106-03-G-S
1
2
3
4
5
6
CC2_G0
CC2_G4
CC lines are connected to the UCPD connection of the ST morpho connectors (CN7 CN10).
Two configurations are possible depending on the CC line connection to ST morpho connectors. To release the
STM32 pins, disconnect unused lines by removing R26/R25 or R24/R27.
An STM32 GPIO manages the TCPP02-M18 (U1) ENABLE PIN. You can also connect it directly to 3.3 V.
1.2.4 5 V only current capability
When the STM32 does not embed the UCPD peripheral, it is possible to manage a 5 V only source. JP2 and JP3
are then connected to CC1-5V and CC2-5V, respectively.
Resistor table 1 and table 2 indicate the 5 V current capability:
• R35/R39 mounted (default configuration): 0.5 A max. at 5 V (36 kΩ pullup to 3.3 V);
• R35/R39 not mounted and SH18/SH20 closed: 1.5 A max. at 5 V (12 kΩ pullup to 3.3 V);
• R35/R39 not mounted and SH19/SH21 closed: 3.0 A max. at 5 V (4.7 kΩ pullup to 3.3 V).
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Figure 9. 5 V only current capability
Resistor table 1
3.3V 3.3V
CC1-5V CC2-5V
R34
4.7k
R39
0
R32
36k
SH20 SH21R35
0
SH18
R36
36k
SH19
R37
12k
R33
12k
R38
4.7k
Resistor table 2
When the STM32 embeds the UCPD peripheral, the STM32 manages the 5 V only sources without an external
pullup resistor (JP2 and JP3 are connected to CC1_UCPD and CC2_UCPD, respectively).
1.2.5 I²C bus
An I²C communication is present between the STM32 Nucleo master port and the TCPP02-M18 (U1) slave port
through the SCL and SDA pins.
The TCPP02-M18 I²C default address is 0x68. You can change it to 0x6A by closing the SH16 solder bridge and
unsoldering R28. The high level is then connected to the I2C_ADD pin of the TCPP02-M18.
The X-NUCLEO-SRC1M1 expansion board embeds two 1kΩ I²C pullup resistors (R11 and R12).
1.2.6 Connection of the voltage/current analog senses to the STM32 ADC
The X-NUCLEO-SRC1M1 has two voltage senses connected to the STM32 ADC:
• ADC_VBUSc: measures the VBUS voltage
Note: It is mandatory to ensure the system operation (for example, vSafe0V measurement).
• ADC_Prov: for information on the provider path voltage.
Voltage dividers (ratio 6) are compatible with 24 V DC voltages.
Figure 10. VBUS voltage sense for the STM32 ADC
ADC_VBUSc
R8
200k
R9
40.2k
The X-NUCLEO-SRC1M1 presents the analog current sense output of the TCPP02-M18 (IANA pin) and connects
it to the STM32 ADC (ADC_Isense).
The TCPP02-M18 has an internal differential amplifier (42 V/V) that measures the current flowing through R5 (7
mΩ).
The capacitor footprints (C9 and C11) have been added for potential filtering on analog senses.
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1.2.7 Consumer and provider path
The provider path can be connected to VBUS thanks to two dual STL40DN3LLH5 N-MOSFETs (Q2) controlled by
the TCPP02-M18 gate driver (SRC and GATE pins).
Figure 11. Provider path
Provider
GND
SOURCE
R22
4k
D7
LED5 blue
GND
GND
GND
ADC_Prov
SOURCE
FLGN
D9
NM
R10
47K
R3
200k
C8
NM
Q2B
D5
G
4
3S
R4
40.2k
R5
0.007
GATE 6
SRC 7
ISENSE
9
VBUSc
8
C9
NM
Q2A
STL40DN3LLH5
D
7
G
2
1
S
CN3
1725656
1
2
Isense
The blue LED (D7) signals the voltage presence on the provider path. This LED does not indicate the N-MOSFET
state. In fact, the source LED D7 can be on to indicate the voltage presence on the provider path but, at the same
time, Q2 can be off (no connection of the provider path on the VBUS).
The CN3 screw connector allows accessing the consumer path. You can add additional protections (transient
or free-wheel diodes) on the D9 footprint that is compatible with the ESDAP series (ESDA7P120-1U1M up to
ESDA25P35-1U1M).
The output current of the TCPP02-M18 gate driver charge pump manages the inrush current. It is associated with
the STL40DN3LLH5 drain to the gate MOSFET capacitance (also called Miller capacitance or reverse transfer
capacitance). This association avoids any potential parasitic OCP triggering due to the inrush current generated
by cSnkBulk (between 1 µF and 10 µF), as defined by the USB Power Delivery standard at attach.
When using another MOSFET reference, the C8 external capacitor can be implemented to another MOS
reference. This implementation avoids the OCP triggering due to the inrush current, in case the drain-to-gate
capacitance is too low. The effective drain-to-gate capacitance including C8 must be higher than 20 pF.
When using a higher cSnkBulk capacitance, close Q2 slower. Then, mount the C8 capacitor, choosing 100 pF for
every additional 10 µF on the cSnkBulk terminal.
1.2.8 Overcurrent protection for VBUS and CC lines
The R5 terminal voltage (voltage between the TCPP02-M18 VBUSc and ISENSE pins) protects the TCPP02-M18
from overcurrent on the VBUS. When this voltage is higher than 0.042 V, the overcurrent protection turns on and
opens the provider path.
Table 1. VBUS currents according to the R5 shunt resistor values
Max. nominal current Overcurrent protection threshold R5 shunt resistor
0.5 A 0.9 A 47 mΩ
1.5 A 1.9 A 22 mΩ
3.0 A 4.2 A 10 mΩ
5.0 A 6.0 A 7 mΩ (default value)
When the overcurrent fault is detected:
• FLGN falls;
• the register 2 is updated;
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• the recovery word is mandatory to get back to an operational system. Recovery words are:
– 0x18 written on the I2C register 0 to return to the normal mode;
– 0x28 written on the I2C register 0 to return to the low-power mode;
– 0x08 written on I2C register 0 to return to the hibernate mode.
The recovery word erases the error register (register 2) but does not connect the consumer or the provider path to
VBUS nor VCONN. Write the corresponding bits to close one or more switches on the additional step.
1.2.9 CC line overvoltage protection
Unplugging a defective cable, with a voltage higher than 5 V, from the USB Type-C™ connector might cause
a VBUS short to the CC lines (adjacent lines). This also might apply a voltage higher than the one specified for
the STM32 AMR on the CC lines (FT IO). The TCPP02-M18 overvoltage protection on the CC lines protects the
STM32.
1.2.10 LDO
The ST715PU33R (U2) is a 3.3 V high input voltage LDO, supplied through the provider path (for example, CN3).
To supply the system with the LDO output, you must close JP1 with:
• a jumper between 1 and 2 to connect the 3.3 V output voltage to the 3.3 V of the system;
• a jumper between 3 and 4 to force the STM32 NRST pin to 3.3 V (otherwise it might cause a potential
parasitic reset).
The D6 green LED signals the 3.3 V presence on the X-NUCLEO-SRC1M1.
Figure 12. LDO configuration
3. 3 V
High input voltage
85 mA LDO linear regulator
GND GND
3.3V
NRST
U2ST715PU33R
IN
1
9
Exp Pad GND
OUT 8
NC1
2
NC2
3
GND
4
NC3 7
NC4 6
FB 5
JP1
TSW-102-07-F-D
1 2
3 4
R23
1k
D8
LED green
C6
470n 5V
1
2
C5
100n 25V 1
2
Provider
GND
SOURCE
R22
4k
D7
LED5 blue
1.2.11 TCPP02-M18 overview
3.3 V is connected to the VCC/VCONN pin of the TCPP02-M18 (U1). It supplies the IC and also provides the
input voltage for VCONN.
VCONN voltage can be in the range of 3.0 to 5.5 V according to the USB-PD standard: VCC/VCONN is compatible
with this voltage range.
All TCPP02-M18 I/Os connected to the STM32 are compliant with 3.3 V and 1.8 V (FLGn, ENABLE, IANA, SDA,
SLC), except CC1 and CC2 I/Os, in which they are in accordance with the USB-PD standard voltages. I2C_ADD
is also compliant with 3.3 V and 1.8 V.
The TCPP02-M18 ENABLE pin is connected to the STM32 GPIO but you can also connect it directly to 3.3 V with
the R29 resistor.
The CBIAS pin capacitor (C3) is the TCPP02-M18 ESD capacitor. Its value must be ≥100 nF and 50 V rated to
limit the voltage derating.
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