ST X-NUCLEO-53L3A2 User manual

Introduction
This document provides detailed hardware information on the X-NUCLEO-53L3A2 expansion board. This expansion board is
compatible with the STM32 Nucleo family and the Arduino™ electronic boards. It is designed around the VL53L3CX ranging
sensor and is based on the ST patented FlightSense technology.
To allow the user to validate the VL53L3CX in an environment as close as possible to its final application, the
X‑NUCLEO-53L3A2 expansion board is delivered with a holder in which three different height spacers of 0.25 mm, 0.5 mm, and
1 mm can be fitted with the cover glass above the spacer. The height spacers are used to simulate different air gap distances
between the VL53L3CX sensor and the cover glass.
The X-NUCLEO-53L3A2 expansion board is delivered with two VL53L3CX breakout boards.
Getting started with X-NUCLEO-53L3A2 multi target ranging ToF sensor
expansion board based on VL53L3CX for STM32 Nucleo
UM2757
User manual
UM2757 - Rev 2 - April 2021
For further information contact your local STMicroelectronics sales office.
www.st.com

Figure 1. X-NUCLEO-53L3A2 expansion board, spacers, cover glass, and breakout boards
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1Overview
The X-NUCLEO-53L3A2 expansion board features the VL53L3CX ranging sensor, based on ST’s FlightSense,
Time-of-Flight (ToF) technology.
It is compatible with the STM32 Nucleo development board family, and with the Arduino UNO R3 connector
layout.
Several ST expansion boards can be stacked through the Arduino connectors, which allows, for example, the
development of VL53L3CX applications with Bluetooth or Wi-Fi interfaces.
The X-NUCLEO-53L3A2 expansion board is delivered with:
• Three spacers of 0.25 mm, 0.5 mm, and 1 mm height, used to simulate different air gaps between the
VL53L3CX and the cover glass.
• Two cover windows to simulate the integration of the VL53L3CX into the customer’s final product.
• Two VL53L3CX breakout boards which can be plugged onto the X-NUCLEO-53L3A2 expansion board or
connected through flying wires to the X-NUCLEO-53L3A2 expansion board.
• Two 10-pin connectors to enable the customer to connect the two breakout boards onto the X-
NUCLEO-53L3A2 expansion board.
Note: The VL53L3CX is delivered with a liner to prevent potential foreign material from penetrating inside the module
holes during the assembly process. This liner must be removed at the latest possible step during final assembly,
before module calibration.
Table 1. Ordering information
Order code Description
X-NUCLEO-53L3A2 STM32 Nucleo expansion board - spacers and glass - two breakout boards
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Overview
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2Document references
Table 2. Document references
Description DocID
VL53L3CX datasheet DS13204
X-NUCLEO-53L3A2 data brief DB4226
P-NUCLEO-53L3A2 data brief DB4194
X-CUBE-53L3A2 data brief DB4193
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Document references
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3X-NUCLEO-53L3A2 expansion board
This section describes the X-NUCLEO-53L3A2 expansion board features and provides useful information for
understanding the electrical characteristics.
Figure 2. X-NUCLEO-53L3A2 expansion board schematic diagram
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X-NUCLEO-53L3A2 expansion board
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3.1 Description
The board allows the user to test the VL53L3CX functionality, to program it and to understand how to develop an
application using the VL53L3CX. It integrates:
• 2.8 V regulator to supply the VL53L3CX
• Level translators to adapt the I/O level to the main board of the microcontroller
• Arduino UNO R3 connectors
• Optional VL53L3CX breakout board connectors
• Solder drops to allow different configurations of the expansion board
It is fundamental to program a microcontroller to control the VL53L3CX through the I2C bus. The application
software and an example of the C-ANSI source code are available on www.st.com/VL53L3CX.
The X-NUCLEO-53L3A2 expansion board and STM32 Nucleo development board are connected through the
Arduino UNO R3 connectors CN5, CN6, CN8, and CN9 as shown in Figure 3. X-NUCLEO-53L3A2 expansion
board connector layout and as described in Table 3. Left Arduino connector and Table 4. Right Arduino connector.
The X-NUCLEO-53L3A2 must be plugged onto the STM32 Nucleo development board through the Arduino UNO
R3 connectors.
Figure 3. X-NUCLEO-53L3A2 expansion board connector layout
1
2
3
4
5
6
CN6
IOREF
+3.3V
GND
1
2
3
4
5
6
7
8
VINP (3V3)
GND
NC
RESET
+5V
VIN
CN9
CN5
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
GND
AVDD
D14
D15
SCL
SDA
INT_L
GPIO1_L INT_L*
NC
INT_R*
NC
GPIO1_R INT_R
CN8
INT U14 GPIO1
INT* U17
Fit
NC
A2
A3
A4
A5
A0
A1
U15
U18
NC
U11
NC U10
10
9
8
7
6
5
4
3
2
1
8
7
6
5
4
3
2
1
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Table 3. Left Arduino connector
CN number VL53L3CX
board Pin number Pin name MCU pin X-NUCLEO-53L3A2 expansion board function
CN6 power
1 NC NC
2 NC IOREF
Not used
3 NC RESET
Power 4 3V3 3V3 3.3 V supply
5 NC 5V Not used
Gnd 6 Gnd Gnd
Gnd
Gnd 7 Gnd Gnd
8 NC VIN
Not used
CN8 analog
1 NC PAO
2 NC PA1
GPIO1 3 INT PA4 Interrupt signal from VL53L3CX on
board soldered device
4 NC PB0 Not used
GPIO1 5 INT PC1 (1)
By default not used, interrupt
signal from VL53L3CX on board
soldered device
6 NC PC0 Not used
1. Depends on STM32 Nucleo board solder bridges, see details in Section 3.3: Solder drop configurations. These interrupt
signals are duplicated, but not used. This offers hardware connection flexibility in case of conflict on the MCU interface
management when the expansion board is used superimposed with other expansion boards. In this case, remove the solder
drop from the used interrupt and instead, fit the solder drop in “NC”.
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Table 4. Right Arduino connector
CN number VL53L3CX
board Pin number Pin name MCU pin X-NUCLEO-53L3A2 expansion board function
CN5 digital
SCL 10 D15 PB8 I2C1_SCL
SDA 9 D14 PB9 I2C1_SDA
8 NC AVDD Not used
Gnd 7 Gnd Gnd Gnd
6 INT_L PA5
Not used
5 NC PA6
4 NC PA7
3 NC PB6
GPIO1_L 2 INT_L PC7 By default not used, interrupt
signal from optional VL53L3CX left
breakout board (1)
GPIO1_L 1 INT_L PA9
CN9 digital
8 NC PA8
Not used
7 NC PB10
6 NC PB4
5 INT_R PB5
By default not used, interrupt
signal from optional VL53L3CX
right breakout board (1)
4 NC PB3 Not used
3 INT_R PA10
By default not used, interrupt
signal from optional VL53L3CX
right breakout board (1)
2 NC PA2
Not used
1 NC PA3
1. These interrupt signals are duplicated, but not used by default. This offers hardware connection of the breakout board
VL53L3CX interrupt signals and flexibility in case of conflict on the MCU interface management when the expansion board
is used superimposed with other expansion boards. In this case, select, through a solder drop, the MCU port which is free.
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3.2 Electrical schematic
Figure 4. X-NUCLEO-53L3A2 expansion board schematic
VL53L3
VL53L1
VL53L3CX application
VL53L3CX
* Can be NC or grounded
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Electrical schematic
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3.3 List of materials
Table 5. List of materials
Components Value Reference Supplier Comments
VL53L3CX application
C1, C3 100 nF X5R
Supply voltage decoupling
C2 4.7 µF X5R - 6.3 V
R1 47 k Interrupt output pull up
R2 47 k Reset input pull up
R66, R67 4.7 k SDA and SCL line pull up at 2.8 V
S1 VL53L3CX ST ToF ranging sensor
VL53L3CX breakout board interfaces
R20 47 k Left breakout board interrupt output
pull up
R21 47 k Left breakout board reset input pull
up
R22 47 k Right breakout board reset input pull
up
R23 47 k Right breakout board interrupt
output pull up
2.8 V regulator application
C8 10 µF X5R - 6.3 V Output voltage decoupling
C9 10 µF X5R - 6.3 V Input voltage decoupling
R35 49.9 k Feedback resistor bridge to set the
output voltage to 2.8 V
R43 20 k
U20 LD39050PUR ST Output programmable regulator
Level translator application
C4, C6, C11 100 nF 2.8 V decoupling capacitor
C5, C7, C13 100 nF
3.3 V decoupling capacitor
C12 1 µF X5R - 6.3V
R68, R69 4.7 k SDA and SCL line pull up at 3.3 V
U3, U9 TXS0108PWR TI For all signals except I2C interface
U24 ST2329AQTR ST For I2C interface
Add-on feature
C10 100 nF Supply decoupling capacitor
R45 4.7 k Push button pull up
R46 1 k Output pull up
R60 Delay time setting (def = 10 ms)
PB1 Push button
U22 TPS3838K33 TI Supervisory circuit
GPIO expander
C14, C15 100 nF Supply decoupling capacitor
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