• Terminal
    Terminal
    An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
  • Ground
    A common return path for electric current. Commonly known as ground.
  • Net Portal
    A net identifier used to create connectivity to other Net Portal with the same designator. #portal
  • Power Net Portal
    Power net portal is a special schematic object used to define a power or ground net. Power ports allow you to conveniently indicate a power net at any location in the design. Power nets of the same designator automatically connect throughout your design #portal #power
  • Generic Resistor
    A generic fixed resistor for rapid developing circuit topology. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard resistor values: 1.0Ω 10Ω 100Ω 1.0kΩ 10kΩ 100kΩ 1.0MΩ 1.1Ω 11Ω 110Ω 1.1kΩ 11kΩ 110kΩ 1.1MΩ 1.2Ω 12Ω 120Ω 1.2kΩ 12kΩ 120kΩ 1.2MΩ 1.3Ω 13Ω 130Ω 1.3kΩ 13kΩ 130kΩ 1.3MΩ 1.5Ω 15Ω 150Ω 1.5kΩ 15kΩ 150kΩ 1.5MΩ 1.6Ω 16Ω 160Ω 1.6kΩ 16kΩ 160kΩ 1.6MΩ 1.8Ω 18Ω 180Ω 1.8KΩ 18kΩ 180kΩ 1.8MΩ 2.0Ω 20Ω 200Ω 2.0kΩ 20kΩ 200kΩ 2.0MΩ 2.2Ω 22Ω 220Ω 2.2kΩ 22kΩ 220kΩ 2.2MΩ 2.4Ω 24Ω 240Ω 2.4kΩ 24kΩ 240kΩ 2.4MΩ 2.7Ω 27Ω 270Ω 2.7kΩ 27kΩ 270kΩ 2.7MΩ 3.0Ω 30Ω 300Ω 3.0KΩ 30KΩ 300KΩ 3.0MΩ 3.3Ω 33Ω 330Ω 3.3kΩ 33kΩ 330kΩ 3.3MΩ 3.6Ω 36Ω 360Ω 3.6kΩ 36kΩ 360kΩ 3.6MΩ 3.9Ω 39Ω 390Ω 3.9kΩ 39kΩ 390kΩ 3.9MΩ 4.3Ω 43Ω 430Ω 4.3kΩ 43KΩ 430KΩ 4.3MΩ 4.7Ω 47Ω 470Ω 4.7kΩ 47kΩ 470kΩ 4.7MΩ 5.1Ω 51Ω 510Ω 5.1kΩ 51kΩ 510kΩ 5.1MΩ 5.6Ω 56Ω 560Ω 5.6kΩ 56kΩ 560kΩ 5.6MΩ 6.2Ω 62Ω 620Ω 6.2kΩ 62KΩ 620KΩ 6.2MΩ 6.8Ω 68Ω 680Ω 6.8kΩ 68kΩ 680kΩ 6.8MΩ 7.5Ω 75Ω 750Ω 7.5kΩ 75kΩ 750kΩ 7.5MΩ 8.2Ω 82Ω 820Ω 8.2kΩ 82kΩ 820kΩ 8.2MΩ 9.1Ω 91Ω 910Ω 9.1kΩ 91kΩ 910kΩ 9.1MΩ #generics #CommonPartsLibrary
  • Generic Capacitor
    A generic fixed capacitor for rapid developing circuit topology. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard capacitor values: 1.0pF 10pF 100pF 1000pF 0.01uF 0.1uF 1.0uF 10uF 100uF 1000uF 10,000uF 1.1pF 11pF 110pF 1100pF 1.2pF 12pF 120pF 1200pF 1.3pF 13pF 130pF 1300pF 1.5pF 15pF 150pF 1500pF 0.015uF 0.15uF 1.5uF 15uF 150uF 1500uF 1.6pF 16pF 160pF 1600pF 1.8pF 18pF 180pF 1800pF 2.0pF 20pF 200pF 2000pF 2.2pF 22pF 20pF 2200pF 0.022uF 0.22uF 2.2uF 22uF 220uF 2200uF 2.4pF 24pF 240pF 2400pF 2.7pF 27pF 270pF 2700pF 3.0pF 30pF 300pF 3000pF 3.3pF 33pF 330pF 3300pF 0.033uF 0.33uF 3.3uF 33uF 330uF 3300uF 3.6pF 36pF 360pF 3600pF 3.9pF 39pF 390pF 3900pF 4.3pF 43pF 430pF 4300pF 4.7pF 47pF 470pF 4700pF 0.047uF 0.47uF 4.7uF 47uF 470uF 4700uF 5.1pF 51pF 510pF 5100pF 5.6pF 56pF 560pF 5600pF 6.2pF 62pF 620pF 6200pF 6.8pF 68pF 680pF 6800pF 0.068uF 0.68uF 6.8uF 68uF 680uF 6800uF 7.5pF 75pF 750pF 7500pF 8.2pF 82pF 820pF 8200pF 9.1pF 91pF 910pF 9100pF #generics #CommonPartsLibrary
  • Generic Inductor
    A generic fixed inductor for rapid developing circuit topology. *You can now change the footprint and 3D model at the top level anytime you want. This is the power of #generics
  • RMCF0805JT47K0
    47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film #forLedBlink
  • 875105359001
    10uF Capacitor Aluminum Polymer 20% 16V SMD 5x5.3mm #forLedBlink #commonpartslibrary #capacitor #aluminumpolymer #radialcan
  • CTL1206FYW1T
    Yellow 595nm LED Indication - Discrete 1.7V 1206 (3216 Metric) #forLedBlink
explain this project.

@copilot explain this project.
1y
This project involves the Seeed Studio XIAO nRF52840 Sense board, a device that combines the nRF52840 microcontroller and some sensors, along with Bluetooth 5.0 wireless capability; it is primarily designed for low-power applications like Internet of Things (IoT) and embedded Machine Learning.
As per the information provided, it appears that there are no nets currently in this project - it's a list of the board's pin designator names along with their corresponding pin numbers:
  1. P0.02_A0_D0 (Pin Number: 1)
  2. P0.03_A1_D1 (Pin Number: 2)
  3. P0.28_A2_D2 (Pin Number: 3)
  4. P0.29_A3_D3 (Pin Number: 4)
  5. P0.04_SDA_A4_D4 (Pin Number: 5)
  6. P0.05_SCL_A5_D5 (Pin Number: 6)
  7. P1.11_TX_D6 (Pin Number: 7)
  8. D7_RX_P1.12 (Pin Number: 8)
  9. D8_SCK_P1.13 (Pin Number: 9)
  10. D9_MISO_P1.14 (Pin Number: 10)
  11. D10_MOSI_P1.15 (Pin Number: 11)
  12. 3V3 (Power source; 3.3V - Pin Number: 12)
  13. GND (Ground reference - Pin Number: 13)
  14. 5V (Power source; 5V - Pin Number: 14)
Given that structuring of the nodes' naming implies these pins might be variously configured as digital input/output, analog input, SPI (Serial Peripheral Interface), and I2C (Inter-Integrated Circuit) data and clock pins.
Based on this information, this project seems to be in the preliminary stages, with no circuits connected to the board yet. Should you plan to design connections, consider refering to these pin designator names for specificity.
1y
can you add the LDC1312 component with the SD pin on pin number 2 and the Interrupt on pin number 1?
1y
For adding the LDC1312 Inductive Touch Sensor to the project, you would first add the component to your design and set up the part properties accordingly.
After that, you would need to connect it to the XIAO nRF52840 Sense board. Unfortunately, the current pinout of the XIAO nRF52840 Sense board does not clearly define an interrupt or SD pin. However, if we treat digital pins as general-purpose, the pins can likely be assigned as per your need.
You can try the following steps:
  • Connect the SD (Shutdown Pin) of the LDC1312 to the P0.03_A1_D1 (Pin number 2 of XIAO).
  • Connect the Interrupt pin of the LDC1312 to the P0.02_A0_D0 (Pin number 1 of XIAO).
For a precise and successful design, it's recommended to verify the pin configurations based on both LDC1312 and XIAO nRF52840 datasheets as well as your application requirements.
Note: Make sure that the voltage levels match between the components to prevent damage - you might need to use a level shifter if necessary.
1y
Someone is typing...
please explain what 3V3 does.

@copilot please explain what 3V3 does.
4mo
Someone is typing...
5
create a detailed step by step plan table for P0.02\_A0\_D0 to verify its functi...

@copilot create a detailed step by step plan table for P0.02_A0_D0 to verify its functionality.
2mo
Someone is typing...
6
How to access solder points for XIAO on back of board for battery

How to access solder points for XIAO on back of board for battery
9mo
Someone is typing...
4
D9_MISO_P1.14
P1.11_TX_D6
P0.29_A3_D3
D8_SCK_P1.13
P0.04_SDA_A4_D4
D7_RX_P1.12
P0.05_SCL_A5_D5
3V3
P0.28_A2_D2
P0.03_A1_D1
P0.02_A0_D0
GND
D10_MOSI_P1.15
5V

Seeed Studio XIAO nRF52840 Sense

Seeed Studio XIAO nRF52840 Sense
Description

Created
November 7th 2023
Last updated by jharwinbarrozo
a year ago
1 Contributor(s)
jharwinbarrozo

Controls

Properties

Part Type
Microcontroller
Manufacturer Part Number
102010469
Manufacturer Name
Designator Prefix
U

Availability & Pricing

DPNStockQty 1
11.4K$15.25
10$44.348
11.4K$15.99
210–48$14.00–$14.79
10$14.70

Assets

Simulation

µs

Simulation Speed

can I import eagle .sch files?
@copilot can I import eagle .sch files?
3mo
Yes, you can import Eagle .sch files into Flux. The process typically involves uploading your Eagle schematic file directly into the Flux project. Once uploaded, Flux will attempt to convert the schematic into a format that it can edit. Keep in mind that some complex designs may require additional manual adjustments after the import to ensure everything is working as expected. If you have any specific questions about the process or run into issues, feel free to ask!
3mo
I only see the pinout, not the whole schematic. How can I see the whole schemati...
@copilot I only see the pinout, not the whole schematic. How can I see the whole schematic including all ICs
3mo
In Flux, when you open a project, you’ll see a workspace where you can view both the schematic and the layout if they are available. If you're currently just seeing the pinout, it might be that the entire schematic hasn't been created yet.
To view the whole schematic, including any ICs and connections:
  1. Check the Project Workspace: Ensure you are on the schematic view, not just the component list.
  2. Add the Components: You need to add components to your workspace. If the schematic isn't fully created, you might need to add ICs and other components manually.
  3. Use the Search Bar: Use the Flux search bar to find specific components or ICs you want to add to your schematic.
  4. Create Connections: Once you've added components, you can create electrical connections between them.
  5. Explore the Layers: Ensure that all layers are visible in your workspace; sometimes certain elements might be hidden.
If you're starting from the pinout, you might need to build out the remaining parts of the schematic manually by adding components and defining connections as described above. Would you like any help with specific components or connections?
3mo
My 3d img is lagging
My 3d img is lagging
5mo
How would i integrate 100mah battery with this??
@copilot How would i integrate 100mah battery with this??
6mo
To integrate a 100 mAh battery with the Seeed Studio XIAO nRF52840 Sense, you'll need to follow these steps:
Components Needed:
  1. Battery holder or connectors compatible with your battery.
  2. Charging circuit (optional but recommended) to safely charge the battery.
Steps:
  1. Locate Battery Pins on the XIAO nRF52840 Sense: Generally, you'll use the voltage input and ground pins.
    • Voltage Input (VCC/5V) Pin: 5V5V
    • Ground Pin: GNDGND
  2. Connect the Battery:
    • Positive Terminal (Battery +): Connect the positive terminal of your battery to the 5V5V input pin.
    • Negative Terminal (Battery -): Connect the negative terminal of the battery to the GNDGND pin.
Example Connections:
  • Connect Battery +: Battery+Battery + to 5V5V
  • Connect Battery -: BatteryBattery - to GNDGND
Optional: Add a Charging Circuit
For a more robust solution, you can add a charging circuit like a TP4056 to safely charge your battery via USB.
  1. Connect the charging circuit to the battery and XIAO nRF52840 Sense:
    • TP4056 OUT+ to 5V5V
    • TP4056 OUT- to GNDGND
    • TP4056 B+ to Battery +
    • TP4056 B- to Battery -
Specific Example Connections:
  • Connect TP4056 OUT+: TP4056OUT+TP4056 OUT+ to 5V5V
  • Connect TP4056 OUT-: TP4056OUTTP4056 OUT- to GNDGND
  • Connect TP4056 B+: TP4056B+TP4056 B+ to Battery +
  • Connect TP4056 B-: TP4056BTP4056 B- to Battery -
Assumptions:
  • Your battery is a typical LiPo battery which has a nominal voltage of 3.7V.
  • You have the necessary connectors to make these connections (e.g., JST connectors for the battery).
Let me know if you need any additional details or if there are specific parameters for your battery setup!
6mo
How would i integrate 100mah battery with this??
@copilot How would i integrate 100mah battery with this??
6mo
there is some metal component on the bottom of the seeed studio xiao nrf52840 s...
@copilot there is some metal component on the bottom of the seeed studio xiao nrf52840 sense, how do I see them in the schematic page?
10mo
In the context of Flux.ai, the electronics CAD program, displaying physical components such as a metal shielding or a heat sink that may be present on the bottom of a hardware module like the Seeed Studio XIAO nRF52840 Sense in the schematic view is not standard practice. Schematics are primarily concerned with representing the electrical connections and components of a circuit rather than its physical attributes or layout specifics.
However, if it is crucial for your design documentation or understanding to note the presence of such physical components, here are some suggestions:
  1. Add a Note or Comment: You can add a text note or comment in your schematic next to the symbol of the Seeed Studio XIAO nRF52840 Sense. This note can specify the presence of the metal component on the bottom of the module. While this doesn’t visually show the component, it makes sure the information is there for reference.
  2. Create a Custom Symbol: If the metal component plays a critical role in your design, for example, as a heat sink or for electromagnetic interference (EMI) shielding, you could create a custom symbol to represent it in the schematic. This symbol can then be placed near the Seeed Studio XIAO nRF52840 Sense symbol. The custom symbol wouldn’t have electrical connections but acts as a visual reminder of the physical component.
  3. Use the Documentation Layer: Some CAD tools, including PCB design features within them, allow for a documentation layer that can include non-electrical elements like outlines, notes, and mechanical components. While Flux.ai focuses on schematic and PCB electrical design, checking if there’s an option to add such non-electrical annotations in a separate layer might be helpful.
  4. Refer to Datasheets and Mechanical Drawings: For detailed physical layout, including positions of non-electrical components like metal parts, it's a good practice to refer to the module’s datasheet and mechanical drawings. These documents often provide detailed diagrams or CAD files showing all aspects of the module, including any significant mechanical components. Including a reference to these documents in your project documentation can also be beneficial.
Remember, the schematic is a tool to convey the electrical design. For the complete representation of both electrical and physical aspects of your project, both the schematic and the PCB layout, complemented with mechanical diagrams if necessary, are required.
10mo
Using the Seeed Studio XIAO nRF52840 Sense, choose an appropriate DAC and develo...
@copilot Using the Seeed Studio XIAO nRF52840 Sense, choose an appropriate DAC and develop a circuit with a 3.5mm audio output with stereo 1v pre outs
10mo
For your project with the Seeed Studio XIAO nRF52840 Sense, which needs to generate a stereo audio signal with 1V pre-outs through a 3.5mm audio jack, a suitable Digital-to-Analog Converter (DAC) is crucial. Considering your requirements, let's proceed with the assumption that you're looking for simplicity in interfacing and good audio performance. A popular choice for such applications is the PCM5102A DAC due to its excellent sound quality, ease of use, and its compatibility with I2S, which the nRF52840 supports natively.
Component Selection:
  • DAC: PCM5102A. It operates well with the 3.3V power available from the XIAO nRF52840 Sense and supports I2S input, which is ideal for audio applications.
  • 3.5mm stereo jack: Any standard 3.5mm stereo jack will suffice, but make sure it has the capability to separate the left and right audio channels.
Connection Overview:
  1. I2S Interface: The nRF52840's I2S interface will connect directly to the PCM5102A's I2S input. This will transmit the digital audio data.
  2. Power Supply: Both the XIAO nRF52840 Sense and the PCM5102A can operate on 3.3V, simplifying the power design.
  3. Output: The output from the PCM5102A will be fed into the 3.5mm audio jack for stereo audio output.
Detailed Connections:
  • I2S Connection:
    • Connect P0.03_A1_D1 (I2S SCK) to PCM5102A:SCK (System Clock)
    • Connect P0.28_A2_D2 (I2S WS) to PCM5102A:LRCK (Left/Right Clock)
    • Connect D10_MOSI_P1.15 (I2S SD) to PCM5102A:DIN (Data In)
    These connections will set up the I2S communication between the XIAO NRF52840 Sense and the PCM5102A.
  • Power Supply:
    • Connect 3V3 to PCM5102A:VCC and to one leg of each 100nF and 1$\mu$F capacitors (for decoupling), with their other legs connected to GND.
    • Connect GND to PCM5102A:GND.
    This will power the PCM5102A DAC with a clean 3.3V supply.
  • Audio Output:
    • Connect PCM5102A:FLT to GND (to select the sharp roll-off filter).
    • Connect PCM5102A:FORMAT to GND (to select the I2S format).
    • Connect PCM5102A:L+ to the left channel of the 3.5mm jack.
    • Connect PCM5102A:R+ to the right channel of the 3.5mm jack.
    • Connect the ground of the 3.5mm jack to GND.
Notes:
  • Ensure you place 100nF and 1$\mu$F capacitors close to the PCM5102A's VCC pin for decoupling.
  • Depending on your power supply's cleanliness, you may want to add additional filtering to the 3.3V supply.
  • You should add a simple resistor and capacitor (RC) low-pass filter at the output of PCM5102A if you encounter any high-frequency noise.
  • Proper PCB layout practices should be followed, especially for the I2S lines and DAC power supply, to minimize noise and interference.
Let me know if you need further assistance with this project, such as PCB layout tips or adjusting the output voltage levels!
10mo
Can you design this pcb in the smallest footprint possible?
10mo
Designing a PCB with the smallest footprint possible requires meticulous planning and optimization of both component placement and routing. While I can't create the PCB layout directly in Flux or any other tool automatically, I can guide you through the strategies to achieve a compact design with the Seeed Studio XIAO nRF52840 Sense and the PCM5102A DAC for your stereo audio output project.
Component Selection for Compactness
  • Choose small package sizes: For the PCM5102A, select a QFN package if available, as it typically occupies less space than TSSOP or other packages.
  • Use small passive components: Opt for 0402 or 0201 passives if your assembly process allows.
Layout Strategies
  1. Place Critical Components First: Position the XIAO nRF52840 Sense and the PCM5102A close to each other to minimize the trace lengths of the I2S lines, optimizing signal integrity and reducing space.
  2. Utilize Both PCB Sides: Place components on both sides of the PCB. For instance, the 3.5mm jack and larger passive components can go on the bottom, while ICs and smaller components are on the top.
  3. Minimize Trace Lengths and Use Vias Efficiently: Short traces reduce interference and save space. Use vias to route signals beneath components as needed.
  4. Optimize Power Routing: Use a common power rail for 3.3V along one side of the PCB to feed both the XIAO nRF52840 Sense and PCM5102A. Ground planes should be maintained as intact as possible for signal integrity.
Additional PCB Design Tips:
  • Decoupling Capacitors: Place them as close as possible to the power pins of both the XIAO nRF52840 Sense and the PCM5102A to minimize loop area.
  • Audio Output: Route the DAC output to the 3.5mm jack with care, avoiding crossing digital signal lines to prevent noise. Consider shielding this trace or using a differential pair if the layout allows.
  • I2S Signal Integrity: Keep the I2S clock, data, and word select lines close together and route them over a solid ground plane. Avoid sharp angles in the traces to reduce signal reflections.
  • PCB Stack-Up: For high-density designs, consider a 4-layer PCB with dedicated power and ground layers to improve power distribution and signal integrity.
Prototype and Testing:
Given the compact design, it's advisable to create test points for critical signals, especially the I2S lines and power supplies, to facilitate debugging. A first prototype run followed by careful testing is recommended to ensure that the design meets both functional and performance criteria.
Final Thoughts:
With meticulous layout planning and using the strategies above, you can achieve a very compact PCB design for the Seeed Studio XIAO nRF52840 Sense and PCM5102A-based audio output project. Remember, the smaller the footprint, the more challenging the assembly might be, so balance compactness with manufacturability based on your capabilities and resources.
10mo
Using the Seeed Studio XIAO nRF52840 Sense, choose an appropriate DAC and develo...
@copilot Using the Seeed Studio XIAO nRF52840 Sense, choose an appropriate DAC and develop a circuit with a 3.5mm audio output with 1v pre outs
10mo
For your project involving the Seeed Studio XIAO nRF52840 Sense with a requirement for a 3.5mm audio output featuring 1V pre-outs, I recommend using the MCP4725 DAC. The MCP4725 is a 12-bit Digital-to-Analog Converter (DAC) with an I2C interface, making it a suitable choice for generating precise analog voltages for audio applications. Given the XIAO nRF52840's I2C capabilities, interfacing with the MCP4725 will be straightforward.
Assumptions:
  • You've requested a 1V output, which implies a line-level output typically used in audio applications.
  • The I2C interface is preferred for simplicity and availability on the XIAO nRF52840 Sense.
  • A standard 3.5mm stereo jack is used, but only mono output will be considered in this design unless specified otherwise.
Components Required:
  • Seeed Studio XIAO nRF52840 Sense
  • MCP4725 DAC Module
  • 3.5mm Audio Jack
  • Resistor: 1kΩ (R1), used for setting the output impedance.
  • Capacitor: 10μF (C1), used for DC blocking at the output.
Connections:
  1. MCP4725 to XIAO nRF52840 Sense:
    • Connect P0.04_SDA_A4_D4:SDAP0.04\_SDA\_A4\_D4:SDA to MCP4725:SDAMCP4725:SDA.
    • Connect P0.05_SCL_A5_D5:SCLP0.05\_SCL\_A5\_D5:SCL to MCP4725:SCLMCP4725:SCL.
    • Connect 3V3:3V33V3:3V3 to MCP4725:VCCMCP4725:VCC.
    • Connect GND:GNDGND:GND to MCP4725:GNDMCP4725:GND.
  2. DAC Output to 3.5mm Jack:
    • Connect the MCP4725:VOUTMCP4725:VOUT through R1:1kΩR1:1kΩ to the TIPTIP of the 3.5mm jack.
    • Connect C1:10μFC1:10μF between R1:1kΩR1:1kΩ and TIPTIP of the 3.5mm jack to block DC. Ensure the positive side of C1 is connected towards the DAC's output.
    • Connect the SLEEVESLEEVE of the 3.5mm jack directly to GND:GNDGND:GND.
  3. Power Connections:
    • Ensure that both the Seeed XIAO nRF52840 Sense and MCP4725 are powered within their operating voltage range.
Schematic Summary:
  • The I2C lines (SDASDA and SCLSCL) of the XIAO nRF52840 are utilized to communicate with the MCP4725 DAC.
  • The DAC's output is conditioned with a resistor and capacitor to match the 1V peak audio signal requirement and block DC offset.
Additional Notes:
  • The MCP4725 module setup in this example will provide a mono audio output. If a stereo output is needed, consider using two MCP4725 modules or a different DAC capable of stereo output.
  • Remember to configure the MCP4725 through the I2C interface to generate the desired analog output. This will involve sending appropriate commands from the XIAO nRF52840 Sense to set the DAC's output voltage.
  • The 1kΩ resistor and 10μF capacitor at the output are crucial for impedance matching and ensuring a clean, DC-free audio signal.
This design should meet your needs for creating a 3.5mm audio output with 1V pre-outs using the Seeed Studio XIAO nRF52840 Sense. If you have any more specific requirements or need further adjustments, feel free to ask!
10mo
Using the Seeed Studio XIAO nRF52840 Sense, develop a circuit with a 3.5mm audio...
@copilot Using the Seeed Studio XIAO nRF52840 Sense, develop a circuit with a 3.5mm audio output with 1v pre outs
10mo
To design a circuit with a 3.5mm audio output with 1V pre-outs using the Seeed Studio XIAO nRF52840 Sense, we first need to consider how to generate and output an audio signal within your specifications. There are multiple methods to achieve this, but one approach involves using a simple DAC (Digital-to-Analog Converter) setup if analog audio output is required directly from the nRF52840. However, given the specifications and the common use-cases, another simpler and more direct approach would be to use the PDM (Pulse Density Modulation) capabilities of the XIAO nRF52840 Sense to generate the audio, assuming a digital microphone interface can be similarly used to output.
Since the XIAO nRF52840 Sense has a PDM interface, we can theoretically make use of this for audio output via software manipulation. For our purposes, we may need to utilize an external DAC for better control over the output voltage and to ensure we have analog audio output if the PDM route proves impractical for direct audio out application.
Basic Circuit Design with External DAC for 3.5mm Audio Output:
  1. External DAC Choice: For simplicity, let's choose a common and easy-to-use I2S DAC module, such as the PCM5102A, which can easily be interfaced with the nRF52840 through I2S, a serial bus interface. This DAC supports output levels we're interested in, with good quality audio output.
  2. Interface DAC with nRF52840:
    • Connect P0.04_SDA_A4_D4P0.04\_SDA\_A4\_D4 (I2S SD, Serial Data) to PCM5102A:DINPCM5102A:DIN (Data Input).
    • Connect D8_SCK_P1.13D8\_SCK\_P1.13 (I2S SCK, Serial Clock) to PCM5102A:BCKPCM5102A:BCK (Bit Clock).
    • Connect D9_MISO_P1.14D9\_MISO\_P1.14 (I2S WS, Word Select) to PCM5102A:LCKPCM5102A:LCK (Left/Right Clock).
    • These connections set up the I2S communication from the XIAO nRF52840 to the DAC. Adjustments might be required depending on the exact DAC module pins.
  3. Power Supply:
    • Connect 3V33V3 to PCM5102A:VCCPCM5102A:VCC.
    • Connect GNDGND to PCM5102A:GNDPCM5102A:GND.
  4. Audio Output:
    • Connect the output of PCM5102APCM5102A to a pre-amplifier circuit if necessary to adjust the output voltage to 1V as required. Pre-amp circuits can be simple op-amp based designs. Ensure the op-amp operates within the 3.3V power supply range.
    • Connect the pre-amplifier output to a 3.5mm audio jack's tip (left audio) and ring (right audio) for stereo output, with the sleeve connected to ground.
  5. Software:
    • Implement the I2S interface on the nRF52840 to output your audio data. The nRF SDK provides examples on how to do this.
    • Given the digital nature of the nRF52840, ensure your audio source is appropriately encoded/digitized for playback.
This basic schematic provides a route to achieve a 3.5mm audio output with control over the output voltage through software and simple hardware. Adjustments may be required based on the exact requirements of your audio source and desired quality.
Please Note: The connections described above are conceptual and should serve as a basis for your design. You might need to adjust connections and components based on your specific requirements and the datasheets of the components you're using.
10mo
Using the Seeed Studio XIAO nRF52840 Sense, develop a circuit involving the SP-3...
Using the Seeed Studio XIAO nRF52840 Sense, develop a circuit involving the SP-3020S soberton speaker and the 3898 adafruit rechargeable lithium ion battery (3.7V, 400mAh) to outputsound from the speaker that changes based on acceleration and displacement of the circuit, where the faster the ball is moving, the faster the sounds pulses, and if the circuit is at ground level the sound makes a double pulse of sound, takes a short break, then double pulses again. I would like the circuit to work for up to 2 hours. Also, if you are able to do so, develop an arduino code for this circuit.
1y
Hey, I’m Copilot, your AI design assistant. I can help you brainstorm ideas, deb...
Hey, I’m Copilot, your AI design assistant. I can help you brainstorm ideas, debug problems, research components, and even make wiring connections for you. Ask me questions like:
  • @copilot I'm designing a PCB for a medical device that measures heart rate and temperature. Can you give me the list of components I will need?
  • @copilot How would I connect these parts to make the LED flash at 1kHz?
  • @copilot can you choose 4 digital pins on the ATMega328P-AU that I have here to use as GPIO given that I am already using some pins for reset, the external clock, UART, and I2C.
Chat with me by tagging @copilot on comments or in the chat.
1y
add a sdcard to thise design
2mo
To add an SD card to your design, you'll need to establish connections between the SD card and the Seeed Studio XIAO nRF52840 Sense. It's common to use the SPI interface for communication with SD cards. Here's how you might proceed with the connections:
Required Connections for SPI Interface
  1. SD Card Pinout: Here's a standard SD card pinout for SPI mode:
    • CS (Chip Select)
    • MOSI (Master Out Slave In)
    • MISO (Master In Slave Out)
    • SCK (Serial Clock)
    • VCC (Power)
    • GND (Ground)
  2. Connections to XIAO nRF52840 Sense:
    • Connect SD_CS to a General Purpose I/O (GPIO) pin on your board. This pin will act as the Chip Select. You might choose $P0.28_A2_D2$.
    • Connect SD_MOSI to $D10_MOSI_P1.15$.
    • Connect SD_MISO to $D9_MISO_P1.14$.
    • Connect SD_SCK to $D8_SCK_P1.13$.
    • Connect SD_VCC to $3V3$ or $5V$, depending on your SD card's voltage requirements. Most SD cards operate at 3.3V.
    • Connect SD_GND to $GND$.
Connection Summary
  • Connect SD_CS to $P0.28_A2_D2$.
  • Connect SD_MOSI to $D10_MOSI_P1.15$.
  • Connect SD_MISO to $D9_MISO_P1.14$.
  • Connect SD_SCK to $D8_SCK_P1.13$.
  • Connect SD_VCC to $3V3$ or $5V$.
  • Connect SD_GND to $GND$.
This setup uses the standard SPI lines. Make sure the logic level of the SD card matches the microcontroller (probably 3.3V), and consider using a suitable voltage level shifter if necessary.
Let me know if you'd like more help with configuring this!
2mo
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