Job Title

Debug Sub-System & Design-for-Test (DFT) Engineer

Summary

We are seeking a Debug Sub-System / DFT Engineer to architect, implement, and validate the on-chip debug and test infrastructure for complex SoC and ASIC designs. This role spans the full lifecycle — from specification and RTL design of debug/DFT features through pre-silicon verification, ATPG pattern generation, and post-silicon validation. The ideal candidate combines deep DFT methodology expertise with knowledge of silicon debug subsystems, enabling efficient manufacturing test, in-field diagnostics, and post-silicon debug.

Key Responsibilities

Debug Sub-System Design & Integration

- Understanding of on-chip debug infrastructure including:
- JTAG TAP controllers (IEEE 1149.1/1149.6) and daisy-chain/star topologies
- CoreSight / ARM Debug Architecture (DAP, SWD, ETM, CTI, cross-trigger matrices)
- Trace infrastructure (ETB, ETR, TPIU, trace funnels, timestamps)
- Embedded Logic Analyzers (ELA) / on-chip signal monitors
- Debug authentication and security (secure debug, debug access levels, lock/unlock)
- Design and integrate DFx (Design for Debug/Diagnostics) features:
- Performance counters and event monitors
- Error logging and first-error capture registers
- Signal observation via debug muxes and pad multiplexing
- Register access over debug ports (JTAG-to-APB/AHB/AXI bridges)
- Debug subsystem interconnect (debug bus, cross-trigger fabric, power-domain-aware debug access)
- Collaborate with architecture teams on debug use cases: boot debug, crash analysis, performance profiling, in-field diagnostics

Design-for-Test (DFT)





- Understand DFT architecture for complex SoC designs, including:
- Scan insertion: full scan, compressed scan (Tessent, Modus, DFT Compiler)
- Memory BIST (MBIST): controller design, repair logic, redundancy allocation
- Logic BIST (LBIST): self-test controllers, PRPG, MISR, fault coverage analysis
- Boundary Scan (JTAG): BSR chain design, IEEE 1149.1 compliance
- At-speed testing: launch-on-shift, launch-on-capture, multi-clock domain handling
- Drive ATPG pattern generation and achieve target fault coverage (stuck-at, transition, path delay, bridging)
- Implement test compression (DFTMAX, Tessent TestKompress, EDT) to reduce test data volume and ATE test time
- Design DFT for low-power: isolation, retention scan, UPF-aware DFT insertion
- Handle analog/mixed-signal test interfaces (ADC/DAC BIST, PLL test modes, SerDes loopback)
- Define and implement test access mechanisms (TAM): wrapper chains, hierarchical test, IEEE 1500 wrappers for IP cores

Verification & Validation (Most Important)

- Verify DFT/debug RTL through simulation and formal methods:
- JTAG TAP compliance tests
- Scan chain integrity checks
- MBIST/LBIST functional verification
- Debug authentication sequence validation
- Run DRC (Design Rule Checks) for DFT:



scan rule violations, clock gating, X-sources, hold-time fixes
- Perform ATPG dry runs and iterate on coverage closure with design teams
- Support post-silicon DFT validation: scan pattern bring-up, MBIST execution, yield debug
- Debug test escapes and drive corrective actions (pattern update, DFT ECO, coverage gap closure)

Manufacturing Test & Yield

- Collaborate with test engineering and ATE teams on test program development
- Optimize test cost: pattern count, test time, multi-site efficiency, compression ratio
- Support yield analysis and diagnosis: failing pattern debug, defect localization, systematic vs. random fail classification
- Develop and maintain DFT documentation: test architecture specs, coverage reports, test insertion guidelines

Required Qualifications

- Education: B.S./M.S./Ph.D. in Electrical Engineering, Computer Engineering, or related field
- Experience: 4–10+ years in DFT, debug subsystem design, or silicon test engineering
- Strong expertise in one or both domains:
- Proficiency in RTL design using Verilog/SystemVerilog
- Experience with industry DFT tools:
- Knowledge of JTAG/IEEE 1149.1 standard and TAP controller state machine
- Experience with ATPG pattern generation, fault models (SA0/SA1, transition, IDDQ), and coverage analysis
- Familiarity with memory test (March algorithms, repair, redundancy, fuse programming)
- Solid scripting skills: Tcl, Python, Perl for tool automation and flow development
- Understanding of SoC integration and multi-IP DFT challenges

📌 Design for Test (DFT) Engineer (Langley)
🏢 HCLTech
📍 Langley