CID Technology & Digital Tools 2 — Questions and Answers
Question 1: Which file format is the industry-standard output from PCB design tools used to define copper layer artwork for PCB fabrication?
- Gerber (RS-274X) (Correct answer)
- DXF
- IPC-2581
- ODB++
Correct answer: Gerber (RS-274X)
Gerber RS-274X is the most widely accepted format for communicating PCB copper layer artwork to fabricators.
Question 2: In PCB EDA tools, what does the 'Design Rule Check (DRC)' primarily verify?
- Signal integrity margins
- Physical spacing and clearance constraints (Correct answer)
- BOM cost estimates
- Power delivery network impedance
Correct answer: Physical spacing and clearance constraints
DRC checks that all physical layout constraints—such as trace-to-trace clearance, minimum trace width, and drill-to-copper spacing—are satisfied.
Question 3: A CID uses a 3D MCAD tool integrated with their ECAD environment. What is the primary benefit of this ECAD/MCAD co-design workflow?
- Automatic BOM generation
- Collision detection between PCB components and mechanical enclosure (Correct answer)
- Automated impedance calculation
- Direct fabrication output without Gerber files
Correct answer: Collision detection between PCB components and mechanical enclosure
ECAD/MCAD co-design allows designers to detect mechanical interference between electronic components and the physical housing early in the design cycle.
Question 4: Which EDA tool feature allows a designer to simulate how signals propagate across differential pairs before committing to layout?
- 3D step model viewer
- Pre-layout simulation with IBIS models (Correct answer)
- Gerber viewer
- Automated test fixture generator
Correct answer: Pre-layout simulation with IBIS models
Pre-layout simulation using IBIS (Input/Output Buffer Information Specification) models estimates signal behavior based on topology and net parameters.
Question 5: What is the purpose of ODB++ format in PCB design?
- A schematic capture file format
- A comprehensive database format for PCB fabrication and assembly data (Correct answer)
- A netlisting format for SPICE simulation
- A 3D rendering format for mechanical enclosures
Correct answer: A comprehensive database format for PCB fabrication and assembly data
ODB++ is a rich, unified format that captures all PCB fabrication and assembly data in a single hierarchical database, replacing multiple separate Gerber and drill files.
Question 6: In a PCB design tool, 'constraint-driven design' means the software:
- Prevents the designer from placing any components manually
- Enforces electrical and physical design rules automatically during layout (Correct answer)
- Generates netlists from simulation results
- Limits the number of routing layers available
Correct answer: Enforces electrical and physical design rules automatically during layout
Constraint-driven design uses a rules engine to enforce electrical (impedance, timing) and physical (spacing, width) constraints in real time as the designer works.
Question 7: Which technology allows a PCB designer to check component placement against a 3D model of the mechanical enclosure directly within the EDA environment?
- IDF (Intermediate Data Format) integration (Correct answer)
- SPICE netlist export
- Drill symbol legend
- Excellon format
Correct answer: IDF (Intermediate Data Format) integration
IDF integration allows exchange of board outline, component height, and placement data between ECAD and MCAD tools for mechanical clearance verification.
CID Technology & Digital Tools 2
Which file format is the industry-standard output from PCB design tools used to define copper layer artwork for PCB fabrication?