Introduction
PADS is a printed circuit board (PCB) design software from Mentor Graphics, used for schematic capture and PCB layout. It provides an end-to-end solution for electronics design, enabling engineers to create complex multi-layer boards and integrate electrical/mechanical co-design.
PADS has a long history spanning over 30+ years of development and is widely used in sectors like automotive, aerospace, industrial, medical, networking and instrumentation. This article provides an overview of PADS – its features, capabilities, applications and role in the PCB design workflow.
Overview of PADS Software
PADS is feature-rich professional EDA software for PCB design targeted at the high-end market. Key attributes:
- Integrated – Unified environment for schematic, layout, routing, library management
- Scalable – Solutions for simple to complex multi-board systems
- High-Speed – Tools for signal integrity, DDR routing, impedance control
- Flexible – Customizable design flow and user interface
- Interoperable – Links with MCAD, analysis, simulation tools
PADS has an array of capabilities geared for efficient PCB design, including:
Schematic Capture
Intelligent tools for drawing and verifying schematics with automation, cross-probing to analyze circuits. Extensive component libraries.
PCB Layout
Modern GUI with high-speed editing, placement, routing. DRC/ERC checks. Constraint-driven, rules-based autorouting.
Library Management
Centralized storage of schematic symbols and PCB footprints. Generation of device models.
High-Speed Design
Tools for signal integrity analysis, impedance control, RF design, IBIS simulations.
Co-Design Integration
Collaboration with MCAD for enclosures, thermal analysis. EMI/signal integrity analysis.
Key Features and Tools
Let’s look at some of the major features and capabilities of the PADS software suite:
Unified Design Environment
PADS has an integrated schematic capture, PCB layout and library management environment for seamless design flow. Engineers can cross select between schematics and layout, cross probe to analyze connectivity, synchronize changes across documents.
Constraint-Driven, Rules-Based Autorouting
The auto-router in PADS is highly advanced, customizable rules-based engine that can handle complex HDI boards, following timing, topology, spacing constraints. This minimizes manual routing.
Design Reuse
PADS facilitates reuse of existing schematic blocks, layout fragments, custom padstacks. This accelerates design by leveraging proven building blocks.
Multi-Channel Design
Engineers can create designs with multiple PCBs in parallel with synchronization, reducing duplication of effort and minimizing errors.
DFM Analysis
PADS integrates DFM analysis tools to assess manufacturability, including design rule checks, copper balancing, layer stack visualization. This avoids costly mistakes.
Signal and Power Integrity
Tools are provided for SI/PI analysis – transmission lines, route impedance matching, IR drop analysis, IBIS simulation. Critical for high-speed digital design.
Documentation
PADS includes extensive capabilities for generating manufacturing documentation – assembly drawings, fabrication outputs, bill of materials, etc.
Open Architecture
PADS is based on open standards to enable integration with various MCAD systems, analysis tools through APIs. Customization using industry-standard languages like Visual Basic, Java, Tcl, Python.
Flexible Licensing
Available as perpetual, term, or cloud subscription licenses. Licenses can be moved between computers or users with offline lease options.
Applications and Markets
PADS software caters to a diverse range of applications across industries like:
Aerospace and Defense – High reliability boards, rigid-flex, advanced packaging
Automotive – Infotainment, RADAR, vision systems, vehicle networks
Medical – Imaging systems, patient monitoring, implants
Instrumentation – Test and measurement equipment
Communications – Networking gear, telecom infrastructure
Industrial – Programmable automation controllers, motor drives
Consumer – Home appliances, IoT products
PADS is the ideal solution for products requiring advanced PCB technologies – high pin count BGAs, HDI stacked microvias, high-speed digital, chip packaging.
Role in PCB Design Flow
PADS plays a core role in the electronics development process:
The typical workflow is:
- System Design – Define product architecture, electronics functionality
- Schematic Capture – Create circuit schematics in PADS
- Simulation – Simulate designs for functional verification
- PCB Layout – Convert schematics to board layout in PADS
- Analysis – Perform signal/power integrity analysis
- Verification – Validate designs with DRCs, ERCs
- Manufacturing – Generate fabrication, assembly files
- Prototyping – Build and test prototypes
- Production – Manufacture final boards
This streamlined, digital flow enables faster design iterations and accelerated time-to-market.
Integrated Solutions
PADS is part of a comprehensive suite of PCB design and analysis solutions from Mentor:
Xpedition – Enterprise design platform for schematic, layout, documentation HyperLynx – SerDes analysis, signal integrity, power integrity BluePrint – PCB documentation, manufacturing outputs
FloTHERM – Multi-physics for thermal design PHYSlcs – Physical layer characterization tool
This provides an integrated toolchain covering the complete PCB product lifecycle. PADS enables collaboration and data exchange between disciplines like electrical, mechanical, thermal, physics layout designers.
Why PADS?
Some of the key reasons why PADS is widely used for advanced PCB design include:
- Mature, proven technology – low risk
- High routing capabilities – less manual effort
- Advanced DFM analysis – reduce respins
- Custom reporting and outputs
- Interoperability and integration
- Scalable – supports simple to complex boards
- Available expertise and training
- Trusted solution from established EDA vendor
Recent Enhancements
PADS continues to evolve with new capabilities:
- Unified 3D/2D design environments
- Electromagnetic analysis integration
- Scripting and programming enhancements
- Cloud-based collaboration
- Virtual reality design reviews
- Machine learning-based design rule assistance
- Integrated requirements management
These innovations expand the functionality and improve user experience.
Conclusion
To summarize, PADS from Mentor Graphics is a sophisticated PCB design software that enables professionals to create complex boards efficiently. Its rich feature set, cutting-edge technologies, interoperability make PADS a top choice for mission-critical electrical and electronic product development.
FQA
What are the key capabilities of PADS PCB design software?
PADS provides integrated schematic capture, PCB layout, autorouting, signal integrity analysis, DFM, library management and documentation capabilities for end-to-end PCB design.
What industries typically use PADS for electronics design?
Key user segments include aerospace, automotive, communications, medical, instrumentation, industrial, and consumer products industries.
How suitable is PADS for designing high-speed digital boards?
PADS has extensive features for high-speed design like impedance matching, IBIS modeling, timing analysis, flexibility to adapt to leading-edge standards.
Can PADS integrate with MCAD and simulation tools?
Yes, PADS has open architecture and APIs to enable integration with MCAD, thermal, electromagnetic field solvers, Spice simulations etc.
What is the learning curve for a new user to become productive with PADS?
An engineer familiar with PCB design can learn PADS quickly. The UI is intuitive and it follows standard ECAD workflows. With training, users can be designing boards within days.