User Defined Rules (Project Rules or Connectivity Verification) are specific technology connectivity rules used for detecting connectivity issues such as Net name and power conflicts, ground and power supply issues, pull-up resistors on open drain outputs, etc. The rules defining objects that need to be connected/not-connected and the connecting
elements are customizable, using a standard Regular Expression description.
BQR has developed pre-defined rules for various technologies such as: Open Drain/ Open Collector Pins, I2C, Crystal, NC pins, PCIe differential, PECL Terminations, Clock AC/TAC and more.

BQR’s fiXtress Schematic Review software implements an automated, innovative approach based on comprehensive knowledge and intelligence, rather than the standard manual approach.
fiXtress  Schematic  Review  uses  Logical  Schematic  Verification  to  automatically  detect  design  errors  using  BQR’s proprietary advanced algorithms, as well as regular Design Rule Checking (DRC), Electrical Rules Checking (ERC) and more.
fiXtress Schematic Review can operate as a standalone module, or complement other fiXtress modules, in order  to provide a comprehensive Design for Reliability (DfR) solution for electrical circuits and PCB design.

Logical  Schematic Review

Most DRC applications provide an abundance of false-positive errors because they focus on the visual aspects of a design (pixels/layout) and use scripts to check the design (scripts are difficult to define and require lengthy run-times).
Logical Schematic Review is based on an abundance of previously unleveraged information that is used to add intelligence, automate the process and minimize false positives.
fiXtress Schematic Review uses the project’s BOM and Netlist (both from popular CAD applications) and predefined part libraries.
This data is used to determine whether components are connected according to proper engineering practices.
For example, fiXtress Schematic Review checks for proper input values (such as sufficient voltage, proper resistance range,sufficient capacitance and so on) and enables engineers to check for a large set of component-based errors.

Checks by BQR fiXtress Schematic Review

  • Pull-up/pull-down resistors
  • Receiver technology matching
  • Power/ground pins
  • Decoupling capacitors
  • Unconnected pins/nets
  • BOM/Netlist comparison
  • Power inputs
  • Many other automated rule checks

fiXtress  Schematic Review  – an Innovative Solution

The design of both small and large PCBs incorporates a significant number of rules, practices and technological concepts, which require a highly complex design review process.
fiXtress Schematic Review simplifies the engineering review process, reduces design time, increases design quality and automatically verifies the implementation of each company’s customized engineering design practices.
fiXtress Schematic Review enables engineers to focus on design functionality by minimizing technical errors before layout,prototyping or fabout.

schematic review flow


Schematic Review Process Flow

BQR’s fiXtress Schematic Review is implemented throughout the design process, so that errors can be fixed at a time when making changes is easy and cost effective.
fiXtress Schematic Review uses the design BOM and Netlist as inputs. In addition, parts library models are uploaded and net names are parsed in order to obtain useful information about the design.
fiXtress Schematic Review uses all input data to analyze the design for errors.
fiXtress Schematic Review also provides an error report that is categorized by severity and details the schematic errors detected in the design. Electronic engineers can then use these reports to prioritize rectifying these errors.