Board components

Featured devices

The board features several NXP ICs:

• MC33772: 6-Channel Li-Ion battery cell controller IC designed for automotive and industrial applications such as HEV, EV, ESS, UPS systems. The MC33772 allows ADC conversions on the differential cell voltages and currents as well as coulomb counting and temperature measurements. It features embedded balancing transistors and diagnostics to simplify applications. The device supports standard SPI and transformer isolated daisy chain communication (via MC33664) to an MCU for processing and control

• S32K144: AEC-Q100 certified microcontroller for general purpose automotive applications. The S32K144 features an Arm® Cortex®- M4F core, 512 KB of Flash, CAN/CAN-FD controllers, security module complying with SHE specification and is offered in LQFP-48, LQFP-64, LQFP-100 and MAPBGA-100 packages supporting an ambient temperature range from -40°C up to 125°C

• UJA1169: Mini high-speed CAN System Basis Chip (SBC) containing an ISO 11898-2:201x (upcoming merged ISO 11898-2/5/6) compliant HS-CAN transceiver and an integrated 5V or 3.3V 250 mA scalable supply (V1) for a microcontroller and/ or other loads. It also features a watchdog and a Serial Peripheral Interface (SPI). The UJA1169 can be operated in very low-current Standby and Sleep modes with bus and local wake-up capability

• A1007: A1007 authentication IC is a secure solution built with many tamper resistant features and security countermeasures to deter common invasive and non-invasive attacks

• NTAG5: NXP’s NTAG 5 boost shrinks the NFC footprint while adding AES security, so designers can deliver ultra-compact devices for use in IoT, consumer, and industrial applications

IC board location identifiers

The main ICs featured are listed in the table below:

Label	Description	Reference
U1	Battery Cell Controller (BCC)	MC33772BSP1AE
U2	Micro-Controller Unit (MCU)	FS32K144HAT0MLFT
U3	System Basis Chip (SBC)	UJA1169TK/F/3
U4	Authentication	A1007
U5	Near-Field Communication (NFC)	NTA53321G10FHK

Connectors

The following figure shows the location of the connectors on the board.

Connectors placements (top and bottom)

All connectors implemented on RDDRONE-BMS772 are detailed in the table below:

Label	Description	Manufacturer	Reference	Placed or DNP
JP1	Cell terminal connector	JST MFG. CO	SxB-XH-A(LF)(SN)	DNP
J1	External temperature sensor	JST MFG. CO	SM02B-GHS-TB(LF)(SN)	Populated
J2	JTAG debugger	-	E.g.: FTS-105-01-F-D from SAMTEC	Populated
J3	CAN bus	JST MFG. CO	SM04B-GHS-TB(LF)(SN)	Populated
J4	Battery power input	-	E.g.: FIT0588 from DFRobot	DNP
J5	Battery power output	-	E.g.: FIT0588 from DFRobot	DNP
J6	Reset jumper	FCI	68000-202HLF	Populated with jumper mounted
J18	SMBus (I²C bus)	JST MFG. CO	SM04B-GHS-TB(LF)(SN)	Populated
J19	DCD-LZ debugger	JST MFG. CO	SM07B-GHS-TB(LF)(SN)	Populated
J20	Additional CAN bus	JST MFG. CO	SM04B-GHS-TB(LF)(SN)	Populated
J21	MCU expansion header	HARWIN INC.	M50-3530842	DNP
J22	Wake jumper	FCI	68000-202HLF	DNP

Note: Hardware configuration of the board is done via 16 jumpers to solder (SJxx). See Cell terminal connection, Shunt resistor and External NFC antenna for more details.

Communication with Flight Management Unit

The RDDRONE-BMS772 board can communicate with a host device such as a PX4 Flight controller (FMU) using the SMBus bus (can also be used as a simple I²C bus, connector J18) or the UAVCAN bus (can also be used as a simple CAN bus, connectors J3 and J20).

Note: For further information about UAVCAN, look for enablement in PX4.io software.

Programming and debug

There are two ways to program and debug the RDDRONE-BMS772 board:

• through the DCD-LZ connector (J19)

• through the JTAG connector (J2)

Note: The DCD-LZ combines a debug interface with a debug serial console. It is used on RDDRONE-FMUK66 (HoverGames). For more information see the HoverGames gitbook.

LED

The RDDRONE-BMS772 implements a programmable RGB LED. Various color combination and blink patterns can be used to indicate the state of the battery and system.

Button

The side button is a wake button, it connects the WAKE pin of the SBC to the ground when pressed. The J22 header placed in parallel of the side button can be used as an alternative if an extended or panel mount button is needed.

External and additional components

External components

An optional external temperature sensor can be added onto the RDDRONE-BMS772 board using connector J1. An example of application for this external sensor can be to monitor the cells temperature inside the battery pack.

Additional components

Some components are included in the design but are not mounted on the RDDRONEBMS772 original board. They are marked "DNP" on the schematics and the BOM. The following table is giving the list of additional components that can be implemented in the design as well as their use:

Feature	Description	Label
Additional MOSFETs	If the application requires more power, two pairs of back to back MOSFETs can be added on the bottom side of the board. Corresponding part is PSMNR70-30YLH. See Configuring the hardware	Q3, Q4, Q7, Q8
Heatsinks	In order to dissipate more power, four additional heat-sinks can be mounted: two on the top side and two on the bottom side of the board. Recommended part is FK 244 08 D2 PAK	HS1, HS2, HS3, HS4
Optional termination resistor network on CAN bus	One 60.4 Ω resistor on each CAN line connected to a 4700 pF capacitor wired to the ground	R49, R50, C66
Capacitors on cell measurements connections	A filter can be added to the cell voltage measurements connections, according to the number of cells in use	C6, C12, C18, C22, C26, C29, C34
Capacitors on external temperature sensor	If the external temperature sensor is implemented, two capacitors can be added on the external temperature sensor low pass filter for more EMC demanding applications	C49, C54
Capacitor on cell balancing connections	Capacitors can be added on the cell balancing circuit for EMC, according to the number of cell in use	C99, C100, C101, C102, C103, C104, C105, C106, C107
External NFC antenna	Coil as an alternative option for the PCB NFC antenna for extended range operations	L2
Resistor on gate driver RS pin	Resistor to link RS pin on gate driver to MCU	R99
MCU expansion header	Additional MCU pins are wired to a 1x8 header slot. Potential to use for local display or additional battery level LEDs	J21
Wake jumper	Jumper for SBC wake-up. In parallel of the button	J22

Test point definitions

The following figure shows the location of the test points on the board.

Test points (Top)

Label	Signal name	Description
TP1	OVERCURRENT	Overcurrent signal
TP2	AUTH_NFC_SCL	Authentication and NFC I²C bus clock signal
TP3	AUTH_NFC_SDA	Authentication and NFC I²C bus data signal
TP4	VCC_3V3_SBC	SBC 3.3 V regulator output
TP5	RST_N	Reset signal (active low)
TP6	CAN_LO	CAN Low signal
TP7	CAN_HI	CAN High signal
TP8	VCC_3V3_LDO1	LDO 3.3 V regulator output
TP9	SMBUS_SCL	SMBus I²C bus clock signal
TP10	SMBUS_SDA	SMBus I²C bus data signal
TP11	VBAT_IN	Power input
TP12	VBAT_OUT	Power output
TP13	GND	Ground reference of the device
TP14	N/A	Power switches gate command
TP15	N/A	Spare test point. J21[2] pin