Project Overview and Design Details
1:40
Project
Below is an overview that breaks down the project from a high‐level perspective:
Purpose and Concept
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Objective:
This example project is intended to demonstrate how the AI Auto Layout feature in Flux can be used to quickly and efficiently route a PCB. The design is built around a smart scale application—illustrating how to integrate sensors, manage power, and handle communications in a compact, modern system. -
Design Philosophy:
The project serves both as an educational tool and as an example for rapid prototyping. It emphasizes the automation of layout tasks by defining rulesets, zones, and fanout strategies so that designers can learn by mimicking the setup in their own projects.
Core Components
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Main Controller:
The heart of the design is an ESP32 microcontroller (ESP32-C3) that provides wireless connectivity, processing power, and interfaces for sensor data acquisition. This MCU handles the logic for reading weight data as well as communicating with other system modules. -
Sensor Interface and ADC:
A precision analog-to-digital converter (NAU7802SGI) is present to accurately read the small signal variations from load cell sensors. This is crucial for obtaining reliable weight measurements. -
Power Management:
- A low dropout voltage regulator (NCP176BMX330TCG) ensures a stable supply for sensitive analog circuitry.
- In addition, a switching regulator (TPS62130ARGTR) is used where efficiency is a priority. Combining both types can help balance low-noise performance (provided by the LDO) with high efficiency (offered by the switcher).
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Clock and Timing:
A crystal oscillator (RH100-40.000-18-F-2030-EXT-TR-NS1) provides timing accuracy for the microcontroller. The stability of the clock is fundamental to the performance of digital circuits. -
User Interface and Connectivity:
Other components such as connectors, test points, and even an antenna (2450AT18B100E) are part of the design to support external communication and ease of debugging. The MicroSD card connector (MSD-4-A) further suggests that the design may include data logging or firmware update capabilities. -
Passive Components:
A wealth of resistors, capacitors, and inductors are distributed throughout the design to:- Condition and decouple supply voltages.
- Provide biasing and filtering in analog signal chains.
- Ensure proper impedance control and layout spacing for high-speed signals.
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Interconnection Primitives:
The design leverages net portals and ground objects (such as the dedicated Ground) to simplify connectivity in the schematic. These serve to reduce wiring complexity and ensure that supplies and signals are consistently distributed.
Design, Implementation, and Functionality
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Schematic Design:
The circuit is built in a modular fashion where each functional block has clearly defined nets—for example, separate power nets (PP5V0, PP3V3, PP12V0) and signal nets (such as I2C lines, SPI lines, etc.). The use of portals streamlines connectivity between disparate sections of the design. -
PCB Layout and AI Auto Layout:
The main highlight of this project is the use of Flux’s AI-based auto layout feature. By setting up rulesets (for trace widths, keepout zones, pad spacing, and via definitions) and defining zones (for high-density areas or sensitive circuits such as the load cell interface), the designer can trigger an automated layout that respects the design constraints. -
Inter-component Communication:
- The ESP32 microcontroller interfaces with the ADC for acquiring load cell data.
- Power management circuits ensure that the analog and digital sections receive regulated supply voltages with minimal noise.
- The crystal oscillator provides precise timing required for communication protocols and processor operation.
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Manufacturing Considerations:
The PCB layout incorporates detailed design rule checks (DRC), as evident from the review categories. Multiple nets, airwire errors, and overlapping copper are flagged for review. The project also demonstrates the use of custom zones and via rules which are essential for modern multi-layer boards. -
Functionality:
In operation, the smart scale is expected to:- Sense weight via load cells connected to the ADC.
- Process and display the weight data through the ESP32 MCU (which may handle wireless transmission as well).
- Manage power efficiently using the combination of linear and switching regulators.
Trade-Offs, Challenges, and Optimizations
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Regulator Choice:
The mixed use of an LDO and a switching regulator is a common trade-off. The LDO provides a low-noise supply critical for analog measurements but can be less efficient. The switcher increases efficiency for digital loads but may introduce switching noise. -
Layout Complexity:
With a large number of interconnecting nets and numerous small passive components in a densely packed PCB, ensuring signal integrity and meeting DRC constraints can be challenging. The AI auto layout feature is designed to help with this—but review of airwires and spacing is still necessary. -
Design Reviews:
The embedded review categories (covering passive components, manufacturing, and design rule checks) are an excellent way to catch issues such as missing footprints, invalid net connections, or potential copper overlaps. -
Performance Considerations:
For an application like a smart scale where precision is key, noise on the analog signals must be minimized. Special attention is given to decoupling, grounding, and careful selection of passive components to ensure accuracy in weight measurement.
Real-World Applications and Future Enhancements
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Applications:
This smart scale design could be applied in areas such as consumer kitchen scales, industrial weight measurement systems, or even IoT-connected health and fitness devices. -
Potential Improvements:
- Layout Optimization: Fine-tuning DRC resolution and further reducing airwire errors can lead to an even more robust design.
- Component Optimization: Exploring higher integration or newer low-power components might improve efficiency and reduce board space.
- Scalability: Additional features—such as wireless updates, better sensor fusion algorithms, or energy harvesting—could be integrated as enhancements.
- Design Robustness: Future revisions may also focus on automated thermal simulation and more advanced impedance control to further improve reliability in high-precision applications.
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Enhancements Using AI Auto Layout:
As designers gain confidence with Flux’s AI auto layout, they can experiment with more complex rulesets and optimize placement to reduce noise, improve testability, and simplify routing for large-scale production.
Summary
This project is an educational example designed to showcase the power and efficiency of AI auto layout in Flux for a smart scale application. It combines a modern ESP32-based processing unit with precision sensing through an ADC, robust power management using both linear and switching regulators, and a carefully orchestrated interconnection scheme—all while adhering to precise manufacturing rules and best practices. The example serves as both a proof of concept and a template for future designs that require a balance between functionality, performance, and efficient layout practices.
By studying this example, one gains insight into modular schematic design, the importance of power integrity and signal routing, and the benefits of leveraging automated design tools to speed up the board layout process while maintaining high manufacturing and performance standards.
Power management selection
Find available LDOs
Efficiency vs. simplicity
367 days
Ready.
PP5V0
R3
Resistance
10k Ω
C7
Capacitance
1u F
C13
Capacitance
1u F
PG_PP5V0
C18
Capacitance
1u F
USBC2.0_D_N
SPI_MISO
PP3V3
SPI_SCK
USBC2.0_D_P
PP3V3_SPI
C15
Capacitance
1u F
SPI_SCK
C5
Capacitance
1u F
INT_ADC_DRDY
PP3V3
GPIO_SW1
C12
Capacitance
1u F
I2C_SDA
GPIO_SW2
SPI_MISO
C24
Capacitance
1u F
PP12V0
SPI_MOSI
I2C_SCL
SPI_CS
C31
Capacitance
.1u F
VOS
PP3V3
SPI_CS
SPI_MOSI
H4
H1
C2
Manufacturer Part Number
OPT
C25
Capacitance
22u F
Y1
R7
Resistance
100k Ω
L1
Inductance
2.2n H
R8
Resistance
953k Ω
IC1
U2
C22
Capacitance
10u F
MCU_TXD
J1
H2
C8
Capacitance
13p F
C21
Capacitance
10u F
J2
H3
C6
Capacitance
1.2p F
R6
Resistance
180k Ω
C30
Capacitance
10u F
L2
Inductance
2.2n H
MCU_RXD
L3
Inductance
2.2u H
MCU_BOOT
C4
Capacitance
13p F
Reviews
- Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portaljharwinbarrozo43.0M
- Wirelessly connects power nets on schematic. Identical to the net portal, but with a power symbol. Used to organize schematics and separate functional blocks. To wirelessly connect power net portals, give them the same designator. #portal #powerjharwinbarrozo11.4M
- 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 #CommonPartsLibraryjharwinbarrozo1.5M
- A generic fixed capacitor ideal for rapid circuit topology development. You can choose between polarized and non-polarized types, its symbol and the footprint will automatically adapt based on your selection. Supported options include standard SMD sizes for ceramic capacitors (e.g., 0402, 0603, 0805), SMD sizes for aluminum electrolytic capacitors, and through-hole footprints for polarized capacitors. 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 #CommonPartsLibraryjharwinbarrozo1.5M
- 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 #genericsjharwinbarrozo15.5k
- An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.Terminal
- 47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film #forLedBlinkjharwinbarrozo1.2M
- 10uF Capacitor Aluminum Polymer 20% 16V SMD 5x5.3mm #forLedBlink #commonpartslibrary #capacitor #aluminumpolymer #radialcanjharwinbarrozo1.2M
- Yellow 595nm LED Indication - Discrete 1.7V 1206 (3216 Metric) #forLedBlinkjharwinbarrozo1.1M
![ESPRSSO32 Smart Scale AI Auto Layout [Example] 5RLV thumbnail](https://img-cdn.flux.ai/eyJidWNrZXQiOiJncmF2aXRvbi1lbGVjdHJpYy1zeW1ib2xzIiwia2V5IjoiZG9jdW1lbnRfYXNzZXRzL0VTUFJFU1NPMzJfU21hcnRfU2NhbGVfM0RfVGh1bW5haWwtY2QxNTI2NjItNjdjMi00MTk4LWJmNjUtNDJiZDk5N2E0ODYyLnBuZyIsImVkaXRzIjp7InJlc2l6ZSI6eyJ3aWR0aCI6MTM2LCJoZWlnaHQiOjEzNiwiZml0IjoiY29udGFpbiIsImJhY2tncm91bmQiOnsiciI6MCwiZyI6MCwiYiI6MCwiYWxwaGEiOjB9fX0sIm91dHB1dEZvcm1hdCI6IndlYnAifQ==)
Learn how to use AI Auto Layout on this ESP32 Espresso Smart Scale! In one click you’ll see AI Auto Layout perform magic. Pay close attention to how we recommend creating rulesets, zones, and fanouts. By copying the setup in this example on your own project, you’ll have a fully routed board in no time!
Properties
Properties describe core aspects of the project.
Pricing & Availability
Distributor | Qty 1 |
|---|
Assets
dxf
ESPRESSO32 Smart Scale Board Outline.dxf
ESPRESSO32 Smart Scale Board Outlinedxf
ESPRESSO32 Smart Scale Antenna Cutout.dxf
ESPRESSO32 Smart Scale Antenna Cutout
ESPRESSO32_Smart_Scale_3D_Thumnail.png
ESPRESSO32_Smart_Scale_3D_ThumnailThumbnailControls
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