Design Correctness

Design Verification

The purpose of Functional Verification of Digital Design is to assure extensive coverage of complex designs, moving beyond the limits of simulation, detecting pre-silicon bugs and characterizing them for the design teams to implement corrections, with the ultimate goal or enabling first pass success of the silicon.

Encore Semi is maintaining and continuously expending a broad panel of expertise including:

  • Test/coverage strategy and testbench design
  • Development of commercial reconfigurable test-benches for complex licensed IP


  • Verilog/SystemC Design Verification – Unit (IP) and Integration Verification
  • Expertise with CPUs (ARM, x86, PowerPC), Memory Controllers (DDR), PCIe, high-speed interconnects (internal & external)
  • Simulation based verification (OVM/UVM Environments)
  • Formal – “100% coverage”
  • Assertions – “self-checking” for any testing


  • RTL mapping to Emulation system (“Big Box” and FPGA)
  • IP prototyping and validation firmware using emulation systems


  • Firmware/Hardware Co-Validation and Firmware Verification
  • Non-RTL based Firmware Verification techniques and system-level Firmware development acceleration


  • Leverage of pre-silicon expertise for quick 1st Silicon bring-up; Speed lab checkout

AMS Verification

A special emphasis is given to continuously expand our expertise in AMS verification for complex mixed-signal interfaces. The increase in complexity, configurability and programmability of the analog-to-digital interfaces, it is becoming critical for the design teams to perform thorough functional verification of these interfaces.

Mixed-signal verification is intended as part of integration sign-off, not a replacement to the analog verification done by the designers. Its primary focus is functional verification in time domain, in complement to the variation across PVT or the frequency response. Analog designers use in parallel the design/verification flow to verify circuit marginality and performance or to characterize the circuitry and parametrics.

AMS Verification techniques are usually based on all the best practices from digital verification: UVM, random vector generation and coverage driven verification. It builds one verification infrastructure, mixed with multiple coding style and netlist. (Verilog, SPICE, SystemVerilog, Verilog-AMS, Verilog-A).  Real Number Modeling can be used for maximum simulation performance in the event-driven simulators. AMS assertions are incorporated and metric-driven methodology is usually recommended.

The results is a cross-domain and configurable verification platform that can be used for full-chip verification.

Encore Semi supports the main tools of the industry:

  • Synopsys UVM-AMS
  • Cadence UVM-MS
  • Mentor Graphics


Encore Semi can provide support to customers in leveraging emulation environments (typically “Big Box” Emulation tools – Veloce, Palladium, ZeBu), to extend beyond simulation limits for Complex Integration Verification

The emulation tools can be used in a various ways:

Fast Simulation:

  • complex “full-chip” protocols (Booting, Reset, Security) at Emulation speeds w/o losing simulation controllability & checking

Slow Silicon:

  • Traditional Post-Si Validation during the Pre-Si timeframe – Validation content & environment 100% ready PRIOR to 1st silicon tapeout

Our team is used to configuring and using the various emulation environment. The expertise of our engineers enable the following capabilities:

  • “Use Case” Validation without waiting for first silicon
  • Use of FPGA to Accelerate the FW/SW Development and System Validation
  • Design Reduction: emulate key structures to reduce/remap
  • ASIC-to-FPGA Remodeling – remodel clocks/memories
  • Partition/Mapping – partition and map to multi-FPGAs

 Post-silicon testing

In complement to its design expertise, Encore Semi has developed post-silicon testing and characterization capability, with an emphasis in specific domains requiring strong hands-on experience and broad knowledge of the relevant standards.

  • High-Speed interfaces and protocols (various SerDes, PCIe gen3/4/5, USB, SATA, etc.)
  • RF front-end, connectivity and radios (Wifi, BT LE, UMTS, LTE-x, MIMO, beam forming, etc.)
  • Enterprise-grade SSD controller testing & benchmark (hardware and firmware)

In order to optimize the test and characterization strategy and enable a 24/7 operation, Encore Semi has developed an expertise in developing sophisticated scripts and software to automate the test lab operations. The challenge is often to dynamically adjust the test sequences in order to avoid being stuck by non-passing tests.