Infineon R 48V BATT Switch10 User manual

User Guide Please read the Important notice and the Safety precautions and the Warnings Rev. 1.0
www.infineon.com page 1 of 46 2022-03-09
UG-2021-20
48V Battery Switch Reference Design
R 48V BATT Switch10
About this document
Scope and purpose
This document describes how to use the 48V battery switch reference design R 48V BATT SWITCH10.
The 48V battery switch reference design shows an implementation of an air-cooled high current disconnect
switch for automotive 48 V batteries with hall sensor and shunt based current measurement using the following
Infineon components:
OptiMOS™-5 Power-Transistors IAUT300N08S5N011 and IAUZ40N10S5N130
48V dual channel high-side MOSFET gate driver 2ED4820-EM with SPI
Hall based current sensor TLE4972-AE35D5
Intended audience
Users of the 48V battery switch reference design R 48V BATT SWITCH10.
Reference Board/Kit
Product(s) embedded on a PCB, with focus on specific applications and defined use cases that can include
Software. PCB and auxiliary circuits are optimized for the requirements of the target application.
Note: Boards do not necessarily meet safety, EMI, quality standards (for example UL, CE) requirements.

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Important notice
Important notice
“Evaluation Boards and Reference Boards” shall mean products embedded on a printed circuit board (PCB) for
demonstration and/or evaluation purposes, which include, without limitation, demonstration, reference and
evaluation boards, kits, and design (collectively referred to as “Reference Board”).
Environmental conditions have been considered in the design of the Evaluation Boards and Reference Boards
provided by Infineon Technologies. The design of the Evaluation Boards and Reference Boards has been tested by
Infineon Technologies only as described in this document. The design is not qualified in terms of safety
requirements, manufacturing and operation over the entire operating temperature range or lifetime.
The Evaluation Boards and Reference Boards provided by Infineon Technologies are subject to functional testing
only under typical load conditions. Evaluation Boards and Reference Boards are not subject to the same procedures
as regular products regarding returned material analysis (RMA), process change notification (PCN) and product
discontinuation (PD).
Evaluation Boards and Reference Boards are not commercialized products, and are solely intended for evaluation
and testing purposes. In particular, they shall not be used for reliability testing or production. The Evaluation
Boards and Reference Boards may therefore not comply with CE or similar standards (including but not limited to
the EMC Directive 2004/EC/108 and the EMC Act) and may not fulfill other requirements of the country in which they
are operated by the customer. The customer shall ensure that all Evaluation Boards and Reference Boards will be
handled in a way which is compliant with the relevant requirements and standards of the country in which they are
operated.
The Evaluation Boards and Reference Boards as well as the information provided in this document are addressed
only to qualified and skilled technical staff, for laboratory usage, and shall be used and managed according to the
terms and conditions set forth in this document and in other related documentation supplied with the respective
Evaluation Board or Reference Board.
It is the responsibility of the customer’s technical departments to evaluate the suitability of the Evaluation Boards
and Reference Boards for the intended application, and to evaluate the completeness and correctness of the
information provided in this document with respect to such application.
The customer is obliged to ensure that the use of the Evaluation Boards and Reference Boards does not cause any
harm to persons or third-party property.
The Evaluation Boards and Reference Boards and any information in this document is provided "as is" and Infineon
Technologies disclaims any warranties, express or implied, including but not limited to warranties of non-
infringement of third-party rights and implied warranties of fitness for any purpose, or for merchantability.
Infineon Technologies shall not be responsible for any damages resulting from the use of the Evaluation Boards and
Reference Boards and/or from any information provided in this document. The customer is obliged to defend,
indemnify, and hold Infineon Technologies harmless from and against any claims or damages arising out of or
resulting from any use thereof.
Infineon Technologies reserves the right to modify this document and/or any information provided herein at any
time without further notice.

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Safety precautions
Safety precautions
Note: Please note the following warnings regarding the hazards associated with development systems.
Table 1 Safety precautions
Caution: The heatsink and the device surfaces of the evaluation or reference board
may become hot during testing. Hence, necessary precautions are required while
handling the board. Failure to comply may cause injury.
Caution: Only qualified personnel familiar with the challenges of handling high
current circuits should plan, install, commission, and subsequently service the system.
Failure to comply may result in personal injury and/or equipment damage.
Caution: The evaluation or reference board contains parts and assemblies sensitive to
electrostatic discharge (ESD). Electrostatic control precautions are required when
installing, testing, servicing, or repairing the assembly. Component damage may
result if ESD control procedures are not followed. If you are not familiar with
electrostatic control procedures, refer to the applicable ESD protection handbooks and
guidelines.
Caution: The evaluation or reference board is shipped with packing materials that
need to be removed prior to installation. Failure to remove all packing materials that
are unnecessary for system installation may result in overheating or abnormal
operating conditions.

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Table of contents
Table of contents
About this document....................................................................................................................... 1
Important notice ............................................................................................................................ 2
Safety precautions.......................................................................................................................... 3
Table of contents............................................................................................................................ 4
1 The kit at a glance .................................................................................................................. 5
1.1 Scope of supply .......................................................................................................................................5
1.2 Block diagram..........................................................................................................................................6
1.3 Main features ...........................................................................................................................................6
1.4 Technical data .........................................................................................................................................7
2 System and functional description........................................................................................... 8
2.1 Getting started.........................................................................................................................................8
2.2 Description of the functional blocks.......................................................................................................9
2.2.1 Power supply......................................................................................................................................9
2.2.2 Power stage........................................................................................................................................9
2.2.3 Precharge circuit ..............................................................................................................................10
2.2.4 MOSFET gate driver..........................................................................................................................11
2.2.5 Shunt based current sensing ...........................................................................................................12
2.2.6 Hall based current sensor ................................................................................................................14
2.2.7 Freewheeling....................................................................................................................................16
2.2.8 Microcontroller interface .................................................................................................................17
2.3 Basic operation......................................................................................................................................18
2.3.1 Operating the switch via buttons and status LEDs .........................................................................18
2.3.2 Operating the switch via command line interface..........................................................................20
2.4 Configuration.........................................................................................................................................23
3 System design.......................................................................................................................27
3.1 Power board ..........................................................................................................................................27
3.1.1 Power board schematics .................................................................................................................29
3.1.2 Power board layout..........................................................................................................................30
3.1.3 Power board bill of material ............................................................................................................32
3.2 Adaptor board .......................................................................................................................................34
3.2.1 Adaptor board schematics...............................................................................................................34
3.2.2 Adaptor board layout.......................................................................................................................37
3.2.3 Adaptor board bill of material .........................................................................................................38
4 System performance .............................................................................................................40
4.1 Thermal performance ...........................................................................................................................40
4.2 Precharging ...........................................................................................................................................41
4.3 Overcurrent detection via shunt resistor .............................................................................................42
4.4 Overcurrent detection with hall sensor................................................................................................43
References....................................................................................................................................44
Revision history.............................................................................................................................45

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The kit at a glance
1 The kit at a glance
1.1 Scope of supply
The 48V battery switch reference design consists of
Power board mounted on a heatsink
Adaptor board in Arduino shield form factor
XMC4700 Relax Kit Lite microcontroller board
Flat ribbon cable for connecting the adaptor board to the power board
Figure 1 48V battery switch power board on heat sink
Figure 2 The 48V battery switch with control board

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The kit at a glance
1.2 Block diagram
The design of the switch revolves around the 2 channel MOSFET gate driver 2ED4820-EM. Channel A is used to
control the power MOSFETs for (dis-)connecting the battery. Channel B drives the MOSFETs for the DC-link
precharge circuit.
In order to improve functional safety there are two diverse methods implemented for current monitoring and
overcurrent protection – shunt based current sensing on the low side and hall based current sensing with the
TLE4972-AE35D5 on the high side.
The switch is controlled by a XMC4700 microcontroller kit which also provides a user interface via USB port.
Figure 3 Block diagram
1.3 Main features
Bidirectional 48V battery switch for continuous currents up to 300 A
Precharge path for capacitive loads (e.g. DC-Link capacitor, EMC filter)
Passive freewheeling (active freewheeling optional)
Shunt based current measurement and monitoring in low side path
Hall based current measurement and monitoring in high side path
Current sensor programmer interface for calibration and configuration of the hall sensor
Over current protection with adjustable thresholds
Pre-installed firmware including command line interface

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The kit at a glance
1.4 Technical data
Table 2 System parameters
Parameter Symbol Comment Value Unit
Board size power board L x W x H Including heat sink 75 x 100 x 31 mm
Board size adaptor board L x W x H 53 x 64 x 19 mm
Operating voltage VBAT 24 … 54 V
Maximum supply voltage Vmax 70 V
Digital supply voltage VDD Provided by microcontroller kit 3.3 V
Continuous Current Capability Imax Forced air cooling 300 A
Combined MOSFET on state resistance RDSON typ. @ 25°C 400 µW
Precharge resistor Rprecharge 10 W
Shunt resistance RShunt 50 µW

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System and functional description
2 System and functional description
2.1 Getting started
Connecting supply and load
The 48 V supply has to be connected to the M6 screw terminals marked “BAT+” and “BAT- “. The BAT- terminal
is the ground reference of the board. The load is connected to the screw terminals marked “LD+” and “LD-“.
For driving high currents use properly sized cables and cable lugs. Use a maximum 9 Nm mounting torque for
tightening the nuts on the screw terminals.
Figure 4 Connecting supply and load
Note: Note: Please ensure the right supply polarity as there isn’t any reverse polarity protection
implemented.
Connecting the microcontroller
To connect the XMC4700 Relax Lite Kit to the power board use the provided flat ribbon cable as shown in
Figure 5.
Figure 5 Connecting the microcontroller board to the power board

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System and f
unctional description
Compatibility with other microcontroller boards
By default, the reference kit comes equipped with the XMC4700 Relax Lite Kit. However, thanks to the adaptor
board in Arduino shield form factor the switch can also be connected to other Arduino UNO compatible
microcontroller boards like the AURIX TC375 Lite Kit.
Note: Since the hall based current sensor is a 3.3 V device this reference kit was designed for a digital
supply voltage of 3.3 V. Therefore, the microcontroller board has to be a 3.3 V type.
2.2 Description of the functional blocks
2.2.1 Power supply
The kit requires two power supplies, the battery voltage VBAT and the digital supply voltage VDD.
VBAT can be provided by a 48 V DC power source, like a 48 V battery or a lab power supply. It supplies the gate
driver 2ED4820-EM and the power stage.
The digital supply voltage VDD is derived from the 3.3 V supply of the microcontroller kit, which is powered via
the USB connector. VDD supplies the digital interface of the gate driver and the hall based current sensor
TLE4972-AE35D5.
Table 3 Functional Range
Parameter Symbol Min. Max. Unit
Battery Voltage VBAT 24 54 V
Logic Supply Voltage VDD 3.1 3.5 V
2.2.2 Power stage
Figure 6 Power stage schematics
The power stage consists of five pairs of best in class OptiMOS™-5 Power-Transistors IAUT300N08S5N011 (80V,
1.1 mW) in common source topology. The common source topology has been chosen because it allows the

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System and functional description
control of the five MOSFET pairs by a single gate driver channel and leaves the second gate driver channel of
the 2ED4820-EM available for the control of the precharge circuit.
The power stage is controlled by channel A of the gate driver. Special care has been taken to ensure an even
current distribution between the MOSFETs. This includes decoupling of the sources of the different MOSFET
pairs by source resistors (R9 … R13) as well as equal trace length for each current branch in the layout.
Figure 7 Even current distribution by equal trace length for each current branch
2.2.3 Precharge circuit
Figure 8 Precharge circuit
Many loads on the 48V power domain have a big capacitance like a DC-link capacitor or EMC filter at their input.
Switching onto an uncharged capacitor will cause a high inrush current, limited only by the ESR of the capacitor
as well as other resistances (cables, connectors, battery) in the system.
The high inrush current may inadvertently trip the overcurrent protection. To avoid this, the capacitor needs to
be precharged before activating the main switch. Therefore, a seperate precharge path is implemented in

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System and functional description
parallel to the power switch. The 2ED4820-EM gate driver channel B is driving a pair of IAUZ40N10S5N130
MOSFETs to turn the prechargarging path ON and OFF. The precharge current is limited by a 10 Wpower
resistor.
At the beginning of the charge pulse the power resistor will see the whole battery voltage. The initial power
dissipation at 48V therefore is as big as:
P= V2
R=(48V)2 10 Ω =230.4 W
However, while the capacitor gets charged, the voltage across the resistor will decay exponentially. In spite of
the large initial power surge the energy of the charging pulse is limited and the resistor will not even get hot.
Nevertheless, a power resistor with high pulse current capability has to be used to withstand the high inrush
current. Wire wound resistors usually can handle a multiple of their DC power rating for short pulses and are
well suited for this application.
The time needed to charge the DC link capacitor is specified by the time constant = of the RC circuit
formed by the precharge resistor and the DC link capacitor. After 5the voltage at the capacitor will have
reached 99.3 % of the supply voltage and the capacitor can be considered fully charged. Assuming a 10 mF DC-
link capacitor we get a precharge time of
 = 5= 5 ∗  = 5 ∗ 10 Ω ∗ 10  = 500 
The energy that will be dissipated in the resistor during that precharge pulse is the same as the energy stored in
the capacitor and can be calculated as
= 1
2=1 2∗ 10  ∗(48 )= 11.52 
According to the specification the resistor can handle five times the rated power for five seconds. This would
amount to 5 * 7 W * 5 s = 175 J and should give us enough headroom for charging even bigger DC-link
capacitors.
A problem however might occur when there is a short circuit or a low ohmic load at the output of the switch
and the precharge switch is engaged. In that case the dissipated power would quickly exceed the resistor rating
and the resistor could be damaged. Therefore, the precharge resistor is monitored by the microcontroller.
Whenever channel B is switched on, the voltage across the resistor is measured and the dissipated power is
calculated. If the power exceeds 5 W the microcontroller starts integrating the power over time to get the
energy in the resistor. As soon as it exceeds 100 J, channel B is switched off.
2.2.4 MOSFET gate driver
The 2ED4820-EM is a gate driver designed for high current 48 V automotive applications, with two powerful
gate outputs that allow to drive many MOSFETs in parallel. It supports the back-to-back configuration, both
common source and common drain topology.
The gate driver generates the supply for the gate outputs with the help of on an integrated one-stage charge
pump with external pump and tank capacitors. Except for the supply and charge pump capacitors there is little
external circuitry needed.
For shunt based current monitoring and overcurrent detection the 2ED4820-EM contains a current sense
amplifier with programmable gain. The voltage drop at the shunt resistor is amplified and the amplified voltage
is provided at the CSO output. The current sense amplifier gain as well as the overcurrent threshold can be
configured by SPI.

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System and functional description
In general, all the extensive diagnosis as well as configuration and control of the gate driver is handled via the
SPI interface.
Figure 9 Dual channel MOSFET gate driver 2ED4820-EM
2.2.5 Shunt based current sensing
With continuous currents up to 300 A power dissipation in the shunt resistor can be a concern. Even with a
shunt as low as 100 µWthis amounts to of 9 W power loss in the resistor. Since we wanted to use SMD mounted
shunts we decided to use two of them in parallel. Of course, this comes to the cost of halving the sensitivity, but
thanks to the programmable gain amplifier implemented in the 2ED4820-EM this can easily be compensated.
Another concern is the parasitic inductance of the shunt. In the event of a short circuit the current is limited
only by the inductance of the cables. Assuming 1 m cable with an inductance of 1 µH, the slewrate dI/dt will be
48 A/µs for a supply voltage of 48V (dI/dT = V/L). The high current slew rate will lead to a voltage drop in the
shunt inductance. This is added to the voltage drop at the resistive part and introduces a measurement error.
According to the datasheet the parasitic inductance of the selected shunt resistor ranges between 0.5 nH and 5
nH. Calculated based on the physical dimensions of the section between the sense terminals it should be about
1.8 nH [1]. For two shunts in parallel the inductance is halved, which amounts to 0.9 nH.
With the given current slew rate this inductance induces an error voltage of
VL=L dI
dt = 0.9 nH 48 A µs = 43.2 mV
which would translate to a measurement error of
 = 


= 43.2 
50 µΩ = 864 !
In order to compensate that error, a RC low pass filter has to be added between the shunts and the gain
amplifier of the 2ED4820-EM. The time constant of that RC filter should be equal to the time constant formed by
the shunt resistor and the parasitic inductance:

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Syst
em and functional description


= 1

Since resistors placed in series to the amplifier inputs will influence the gain factor they should be kept as small
as possible. With a chosen filter resistor value of R = 8.2 Wwe get a capacitor value of
   
 =  50 µΩ 8.2 Ω  
Because the current distribution between the two shunts may be unequal, the two shunt voltages may differ
and therefore need to be balanced. This can be achieved by the compensation network shown in Figure 10. In
this circuit the voltage across the capacitor is the arithmetic mean value of the two shunt voltages while the RC
filter time constant remains the same.
Figure 10 Paralleled shunt resistors with parasitic impedance compensation
The chosen shunt resistors don’t have separate sense pins. Instead there is only a recommendation in the
datasheet on where to attach the sense lines to the footprint of the shunt. If you follow this recommendation
the voltage drop in the solder connection between the PCB pad and the shunt would be part of the sensor
signal. Since we are using very low ohmic shunt resistors, every µWwould add an additional measurement
error. Therefore, the footprint of the shunt was modified by introducing separate power and sense pads.
Figure 11 Improved connection of sense lines

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System and functional description
2.2.6 Hall based current sensor
In addition to the shunt based current measurement there is a hall based current sensor implemented to
provide an alternative current monitoring path for improved functional safety. It is located on the high side,
directly after the BAT+ input terminal. Thanks to the intrinsic galvanic isolation of the TLE4972-AE35D5 there is
no need for additional isolators or level shifters. It can be directly connected to the microcontroller. The sensor
offers two analog outputs for differential current measurement and two digital outputs for fast overcurrent
detection with programmable thresholds.
Figure 12 Hall based current sensor TLE4972-AE35D5 with peripheral components
The sensor itself actually measures the magnetic field caused by a current conductor. Only in conjunction with
that conductor (or current rail) it becomes a current sensor. In our case the conductor is a short piece of PCB
trace in the middle layer right below the sensor where all the load current is forced through. The trace is only
3 mm wide but also only 1 mm short and 800 µm thick, with a resistance of only 7 µW. The resulting power
dissipation therefore is 7 times smaller than that of the shunt resistors.
Two hall probes in the sensor measure the magnetic field around the conductor differentially. This ensures high
robustness against stray magnetic fields.
To avoid disturbances due to eddy currents in adjacent conductors the area beneath the current rail is kept free
from metal. That means that there is a cutout in the bottom layer around the current rail as well as a milled-out
area in the heatsink below that structure (see Figure 29 and Figure 34).
Figure 13 Hall sensor placement above current rail in middle layer

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System and functional description
At the location of the hall probes this structure yields a magnetic field strength of ~45 µT/A. This so-called
current rail transfer factor can be determined either by simulation or by measuring the output voltage of the
hall sensor at a given current and using the selected sensitivity range value from the data sheet (in mV/mT) to
calculate the transfer factor in µV/A.
The TLE4972-AE35D5 can be configured and calibrated on board by programming the sensor internal EEPROM
with the TLE4972 current sensor programmer kit1, which can be connected to the adaptor board as shown in
Figure 14.
Figure 14 Connection of the current sensor programmer
The hall sensor on each board is calibrated and set to the following values:
Table 4 TLE4972-AE35D5 Configuration
Parameter Setting Value
Output Mode Fully differential
Sensitivity Range S2 46.5 mV / mT
OCD1 Threshold 6 389 A
OCD2 Treshold 10 246 A
Sensitivity (single ended) 2.4 mV/A
Sensitivity (fully differential) 4.8 mV/A
According to the data sheet full scale for the TLE4972-AE25D5 is defined as 1200 mV in single ended mode and
2400 mV in fully differential mode, which amounts to a default measurement range of ±500 A.
Due to the orientation of the sensor in respect to the current flow, a current flowing from positive supply to
ground will be reported as a negative current on the analog output.
1Order name: „CUR SENSOR PROGRAMMER“, Order number: SP004441438

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The fast overcurrent detection output OCD of the current sensor can be connected to the SAFESTATEN pin of
the gate driver in order to provide a second switch off path for overcurrent events. To enable this functionality
the solder jumper on the adaptor board has to be bridged as shown in Figure 15.
Figure 15 Solder jumper on adaptor board to connect OCD1 to SAFESTATEN
Note: For calibration of the current sensor the solder jumper needs to be open, because the OCD1 may
be pulled low during calibration, which would cause an unintended switch off via the SAFESTATEN
signal.
2.2.7 Freewheeling
When the MOSFETs are switched off, the sudden drop in current flow will induce a large voltage in the output
inductance which pulls the output (LD+) below ground potential (LD-). To protect the switch MOSFETs against
overvoltage a freewheeling MOSFET (Q13) is placed between LD+ and LD-.
Figure 16 Freewheeling MOSFET
Due to its intrinsic body diode, the MOSFET allows freewheeling without beeing switched on. Nevertheless, the
gate signal is routed to the interface connector to provide the option to add an active control circuit.

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2.2.8 Microcontroller interface
The 20-pin connector X11 provides the interface of the power board to the microcontroller. For the connector
pin assignment see Table 5 below. Figure 18 shows the port and pin assigment of those signals for the
microcontroller.
Figure 17
Table 5 Pin Assignment Microcontroller Interface Connector
PIN Label Function
1 VREF TLE4972- AE35D5 Reference Voltage (Output)
2 AOUT TLE4972- AE35D5 Analog Out
3 VDD_S TLE4972- AE35D5 Sensor Supply
4 OCD1 TLE4972- AE35D5 Overcurrent Detection Output 1
5 GND_S TLE4972- AE35D5 Sensor Ground
6 OCD2 TLE4972- AE35D5 Overcurrent Detection Output 2
7 NTC1 Thermistor
8 VLD_F Load Voltage
9 VBAT_F Battery Voltage
10 FW Freewheeling (Gate of freewheeling MOSFET)
11 SAF 2ED4820-EM SAFESTATEN (Safe State Enable)
12 INT 2ED4820-EM INT (Interrupt)
13 SCLK 2ED4820-EM SCLK (SPI Clock)
14 CSN 2ED4820-EM CSN (SPI Chip Select)
15 MOSI 2ED4820-EM MOSI (SPI Master Out Slave In)
16 MISO 2ED4820-EM MISO (SPI Master In Slave Out)
17 EN 2ED4820-EM EN (Enable)
18 VDD 2ED4820-EM VDD (Digital Supply Voltage 3.3 V)
19 CSO 2ED4820-EM CSO (Current Sense Output)
20 GND Ground

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Figure 18 Port and pin assignment XMC4700 Relax Lite Kit
2.3 Basic operation
2.3.1 Operating the switch via buttons and status LEDs
The switch can be controlled by the buttons mounted on the XMC4700 Relax Lite Kit. Several LEDs provide
status and diagnosis information. For extended configuration, control, and diagnosis there is a command line
interface available (see chapter 2.3.2).
After power-up or after a reset the microcontroller will load the driver configuration from the internal flash. The
configuration can be changed by the user (see chapter 2.4 Configuration).
Figure 19 Buttons on XMC4700 Relax Lite Kit

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Table 6 Button functionality
Button Function Description
RESET Reset Microcontroller reset
BUTTON2 Safestate Pull SAFESTATEN pin low to initiate the 2ED4820-EM safe state
BUTTON1 ON/OFF Switch on or off, including initialisation and precharge
If failure occurred (error LED on): clear failure flag
Switching on
When the switch is off and button 1 is pressed, the driver is enabled and initialized with the configuration
settings. Then the precharge path (channel B) is switched on for the configured precharge time to charge up the
load capacitor. When the precharge time is expired, the power switch (channel A) is activated and the
precharge path is switched off.
The status of the 2ED4820-EM outputs channel A (power switch) and channel B (precharge path) is displayed by
the respective status LEDs on the adaptor board. LED1 next to button 1 on the XMC Relax Lite Kit shows the
status of channel A.
Switching off
When the switch is on and button 1 is pressed, both channels are switched off and the driver is disabled.
Clearing failures
In case of a failure the error LED will light up. The failure flag can be cleared by pressing button 1.
Safestate
Pressing button 2 will initiate the safe state functionality of the gate driver 2ED4820-EM. Safe state is indicated
by LED2 next to this button.
Figure 20 Location of Status LEDs

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2.3.2 Operating the switch via command line interface
The firmware of the XMC4700 microcontroller provides a simple command line interface for extended
configuration, control, and diagnosis of the 48V Battery Switch. To use it a standard terminal emulator program
for serial port communication like TeraTerm or PuTTY is needed.
The command line interface uses a virtual COM port via the USB interface for communication. The COM port
gets assigned automatically when the USB cable to the XMC4700 Relax Lite Kit is plugged in. To locate the COM
port number on a Windows PC, check the port assignment in the device manager (Figure 21). The assigned
virtual COM port number is shown in brackets next to the port named “JLink CDC UART Port”.
Figure 21 Locating the virtual COM port in the device manager
Following settings have to be set in the terminal emulator for the serial port communication:
Baud Rate: 115200 bps
8 data bits
No parity bits
1 stop bit
Figure 22 Virtual COM port settings
The terminal window size should be at least 100 characters wide to avoid line wrapping.
After power-up or reset a welcome message and a command prompt is displayed