Complete Learning Module

Hardware Engineering

ISO 26262-5: Designing safe automotive hardware with quantitative integrity metrics

16
In-depth chapters
ISO 26262-5
Standard coverage
SPFM/LFM
HW integrity metrics
PMHF
Probabilistic target

What You'll Learn

Build complete competency in hardware engineering through structured, progressive learning.

Derive HW safety requirements

Translate Technical Safety Concept requirements into specific, testable hardware safety requirements

Calculate HW metrics

Accurately compute SPFM, LFM, and PMHF for automotive hardware designs against ASIL A-D targets

Design safe architectures

Create hardware architectures with appropriate safety mechanisms and redundancy for the required ASIL level

Perform hardware DFA

Identify and mitigate dependent failures including common cause and common mode failures in hardware designs

Qualify ASICs and FPGAs

Apply ISO 26262 requirements to programmable hardware development with appropriate HDL analysis and verification

Pass hardware assessment

Prepare a complete FMEDA, hardware metric report, and DFA package that satisfies independent assessor requirements

16 Comprehensive Chapters

Each chapter builds your hardware engineering expertise systematically from foundations to advanced application.

1

Overview

Introduce ISO 26262-5 as the hardware engineering part of the standard and its role in the overall safety lifecycle.

Part 5 scopeHW development V-modelKey work productsRelationship to Part 4 and 6
2

ISO 26262-5 Framework

Map the normative requirements of Part 5 to hardware development activities and identify mandatory vs. recommended methods.

Normative structureMandatory requirementsMethod tablesTailoring options
3

HW Safety Requirements

Derive hardware safety requirements from the Technical Safety Concept and manage them through the hardware development lifecycle.

Requirement derivationHSR classificationTraceability managementCompleteness criteria
4

Architectural Design

Design the hardware architecture to achieve the required ASIL capabilities, including safety mechanism allocation and channel definition.

Architecture patternsSafety mechanism allocationChannel definitionSafe-state design
5

HSI Specification

Specify the Hardware-Software Interface (HSI) to ensure that software safety requirements are correctly addressed at the hardware boundary.

HSI contentRegister-level specificationTiming constraintsSW-HW handshake
6

Element Selection

Select hardware elements with appropriate failure rate data, qualification status, and proven-in-use records for safety-relevant designs.

Component qualificationFailure rate sourcesProven-in-use criteriaCOTS evaluation
7

Detailed Design

Develop detailed hardware designs with schematic, BOM, and layout considerations that implement and protect safety mechanisms.

Schematic guidelinesComponent deratingLayout constraintsThermal analysis
8

Implementation

Manage hardware implementation including PCB manufacture, assembly, and first-article inspection with safety-relevant process controls.

Manufacturing processFirst-article inspectionProcess controlsNon-conformance handling
9

SPFM/LFM/PMHF Targets

Calculate Single-Point Fault Metric, Latent Fault Metric, and Probabilistic Metric for Hardware Failure (PMHF) against ASIL targets.

SPFM calculationLFM calculationPMHF budgetTarget table by ASIL
10

Safety Mechanism Integration

Integrate hardware safety mechanisms including watchdogs, voltage monitors, ECC memory, and redundant signal paths into the design.

Watchdog circuitsVoltage supervisionECC and parityRedundant channels
11

DFA for Hardware

Perform Dependent Failure Analysis for hardware to identify common cause and common mode failures that could defeat redundancy.

DFA scopeCommon cause failuresCommon mode failuresBeta factor estimation
12

ASIC/FPGA Development

Apply ISO 26262 requirements to ASIC and FPGA development, including IP qualification, HDL coding guidelines, and synthesis verification.

ASIC safety processFPGA qualificationHDL coding rulesFormal verification
13

PCB Design & EMC

Address PCB-level design guidelines and EMC considerations that affect hardware safety integrity in automotive environments.

PCB layout for safetyEMC design rulesDecoupling strategyGuard ring usage
14

HW-SW Integration

Manage hardware-software integration testing to validate that safety mechanisms implemented in hardware are correctly triggered and handled by software.

Integration test planningFault injection testingHSI validationSafety mechanism testing
15

Verification & Test

Plan and execute hardware verification activities including design reviews, analysis, and physical testing to demonstrate safety requirement compliance.

Verification methodsDesign review checklistEnvironmental testingHALT/HASS
16

Best Practices

Consolidate hardware engineering best practices for ISO 26262 compliance including FMEDA efficiency techniques and assessor expectations.

FMEDA best practicesMetric calculation toolsAssessment preparationCommon findings
ISO 26262-5

6 Hardware Engineering Diagrams

Experiment with visual tools that bring hardware engineering concepts to life.

HW Development V-Model

Complete hardware development V-model from HSR derivation through architectural design, detailed design, and integration to verification

SPFM/LFM Calculation Flow

Step-by-step calculation flow for SPFM and LFM from component FMEDA failure mode classification to metric computation against ASIL targets

Safety Mechanism Coverage

Diagram showing how hardware safety mechanisms provide diagnostic coverage for single-point and latent faults across the design

DFA Common Cause Map

Annotated hardware block diagram identifying potential common cause failure sources including shared power rails, ground planes, and thermal coupling

PMHF Budget Allocation

Tree diagram showing PMHF budget allocation from system-level target through subsystems and components with residual and tolerable values

HW-SW Interface Specification

Layer diagram showing HSI elements including register maps, interrupt lines, and diagnostic status signals with ASIL level tagging

ASIL D Hardware Case

Radar ECU Hardware Development for ADAS

An automotive supplier developed an ASIL D radar processing ECU for autonomous emergency braking. The FMEDA identified that the initial architecture had SPFM of only 96.8%, below the 97% ASIL D target. Addition of a dedicated CPU lockstep monitor raised SPFM to 98.4%.

  • FMEDA covered 847 component failure modes across 23 ICs and 340 passives
  • PMHF of 1.8 × 10⁻⁸/h achieved against ASIL D target of < 10⁻⁸/h at item level
  • DFA identified 4 common cause failure scenarios addressed with physical separation
  • Hardware verified with 1,200 fault injection test cases achieving 98% safety mechanism coverage

FMEDA Template

Component: µC Core - Failure Mode: CPU lockup - DC: 99% - Classification: SPF
846 additional FMEDA rows (unlock Advanced plan)

Master ISO 26262 Hardware Engineering

Build the technical expertise to design, analyze, and verify automotive hardware systems to ISO 26262-5 requirements

Start Learning Now
16 chapters6 HW engineering diagramsSPFM/LFM/PMHF calculation