In-Circuit Test (ICT) Analysis Josh Akman (Technical Staff – Mechanical Engineer)

REALLY COOL CASE STUDIES! What is ICT? ICT overview in Sherlock REALLY COOL CASE STUDIES! How is ICT tool useful for you?

What is In-Circuit Test (ICT)? Tool to inspect for manufacturing defects Test probes + support fixtures Exerts a mechanical force at each probe/support Can cause an overstress condition if there is excessive board flexure Pad cratering, flex cracking “Bed of Nails” R. Reinosa, “Characterizing Mechanical Performance of Board Level Interconnects for In-Circuit Test,” International Test Conference (ITC), Austin, TX, November 2-4, 2010.

Evaluate risk of overstress Quickly compare design changes Capacitor Flex Crack ICT tool in Sherlock Evaluate risk of overstress Quickly compare design changes Case Studies Conventional ICT 4 Point Bending Vertical Connector Insertion Horizontal Connector Insertion Pad Cratering

CONVENTIONAL ICT

CASE STUDY 1: CONVENTIONAL ICT Open circuit card layer viewer Define your fixture supports + test probes Circuit Card Layer Viewer Test Probe ICT Fixture Test Probe

Define your fixture supports + test probes Fixture Support Definition Test Probe Definition

ICT Fixture Support vs Mount Points (look identical) Support fixtures override mount points in ICT Fixture Support Definition Mount Point Definition Mount Point ICT Fixture

View deflections and boards level strains

Quickly assess risk of overstress from ICT or depaneling Quickly change probe forces, support locations, or test probe locations

LIVE DEMO!

4 POINT BENDING

CASE STUDY 2: 4-POINT BENDING ICT fixtures – ‘z-only’ pin supports on bottom side Test point – top side loading in displacement control ICT Fixtures Test Probes

Test probes and ICT fixtures can be imported CSV or XLSX files

Support pins + displacement control probes Fixture Support Definition Test Probe Definition

See which components are at risk of overstress

VERTICAL CONNECTOR INSERTION

CASE STUDY 3: VERTICAL CONNECTOR INSERTION Test Points – concentrated loads applied at each pin ICT Fixtures – corners (mount points) Samtec Connecter ICT Fixture Load control 4 [N/pin]

Define test points and fixtures

Resulting board level displacements and strains Quickly iterate and compare results (i.e. insertion force, support locations)

Sherlock identifies critical components at risk of overstress Four 2512 resistors near connector identified as marginally at risk for overstress 4[N/pin]

What if we change connector insertion force to 2[N/pin]?

HORIZONTAL CONNECTOR INSERTION

CASE STUDY 4: USB (HORIZONTAL) INSERTION Ex: JAE USB C P/N – DX07S024JJ3R1300 USB created as and attached as daughter card Test points –applied to USB daughter card

USB modeled as a daughter card Fixture supports – mother card at mount points Test points – defined on USB daughter card 2[N/pin] and 5[N/pin] compared Side view of USB Test points

2[N/pin] insertion force Board level displacements and strains for each component

What happens if we switch to 5[N/pin] insertion force?

How is ICT tool useful for you? Time & Money vs. Accuracy Ideal = Sufficiently Accurate + Least Resource Intensive https://www.labourpower.com/news/recruitment-save-time-money/17541/

How is ICT tool useful for you? Burn In/Test Every Unit vs. Batch Lot Testing How may units will you manufacture? Test Every Unit. Most accurate, resource intensive Screens (ICT, Burn-in). Useful but may apply some initial damage Batch testing. Less resource intensive/damaging but has more risk of missing manufacturing defects Implementing Sherlock ICT tool is a strong complement to provide rapid feedback and reduce need of physical analysis Fast Iterative Feedback. Results in minutes & hours, not days and weeks

Development Cycle Reduce Product How is ICT tool useful for you? Virtual Qualification Concept Validation. Rapidly compare and eliminate designs (i.e. reduce testing, physical sample analysis) Design Validation. Connector insertion & placement, 3/4 point bending, PCBA mounting within your housing Manufacturing. Assess ICT overstress risk, refine test probe forces, select ICT fixture supports, and assess depaneling Development Cycle Reduce Product

How is ICT Tool useful for you? If you remember one thing from this presentation! What is ICT? ICT overview in Sherlock Really cool case studies How is ICT Tool useful for you? Rapidly compare designs and identify risk Get accurate answers within your resource constraints Reduce overall product development cycle

Questions?