IEEE P1149.8.1 Selective Toggle Fault Detection and Isolation Steve - - PowerPoint PPT Presentation

▶

Feb 25, 2023 277 likes •369 views

IEEE P1149.8.1 Selective Toggle Fault Detection and Isolation Steve Butkovich Cisco Systems, Inc . y , Goal of the Fault Evaluation Goal of the Fault Evaluation Using the faults Using the faults portrayed in figure 6 expand on the

SLIDE 1

IEEE P1149.8.1 Selective Toggle Fault Detection and Isolation

Steve Butkovich – Cisco Systems, Inc. y ,

SLIDE 2

Goal of the Fault Evaluation Goal of the Fault Evaluation

Using the faults

Using the faults portrayed in figure 6 expand on the “Table expand on the Table 1 — Potential defects for the circuit in for the circuit in Figure 6” chart

SLIDE 3

Detection Circuit

Stolen from

Low impedance input O ti i d f O Pi D t ti Optimized for Open Pin Detection All pins share a common input through the detection plate

SLIDE 4

Opens Detection p

Open Pin 1 Reduced signal at sense Pin 2 Reduced signal at sense Pin 3 Reduced signal at sense Pin 4 Reduced signal at sense Pin 5 Reduced signal at sense Pin 6 Reduced signal at sense

20.0 25.0

C (£F)

0.0 5.0 10.0 15.0 100 200 300 400 500 600 700 800 900

Open Pin Average Separation in microns 0.5 mm facing area

SLIDE 5

Single Ended Shorts Detection P G d Power or Ground

Primary Detection Method EXTEST with Self Monitoring Capabilities

Short

Secondary Detection Method Capacitively coupled signal reduction Not clear that linearity constraint

Pin to GND/PWR Pin 1 Reduced Signal at Sense Pin 2 Reduced Signal at Sense

Not clear that linearity constraint would provide repeatable test Tertiary Detections Method S k d Fl Smoke and Flames

SLIDE 6

Single Ended Shorts Detection P G d Power or Ground

Unpowered VTEP with induced shorts 100 80 90 100 50 60 70 VTEP No Short 30 40 50 VTEP No Short VTEP Short to GND VTEP Short to Vdd 10 20

Short induced

n pin

Short induced

n pin

1 2 3 4 5 6 7 8 9 10111213141516171819202122232425

SLIDE 7

Differential Shorts Detection P G d Power or Ground

Primary Detection Method EXTEST with independent Self M it i C biliti Monitoring Capabilities

SLIDE 8

Component Short, Open, Value p , p ,

Open Short Wrong Value R1 NOT FOUND Reduced Signal at Sense NOT FOUND R2 NOT FOUND Reduced Signal at Sense NOT FOUND C1 Reduced Signal at Sense NOT FOUND NOT FOUND C2 Reduced Signal at Sense NOT FOUND NOT FOUND C3 Reduced Signal at Sense NOT FOUND NOT FOUND