1. Reliability and Safety Analysis
Digi-Brush
Reliability and Safety Analysis
Presenter: Josh Long
Team Members:
Katie Schremser
Caleb Ayew-ew

2. Components to Analyze
FPGA
Microcontroller
Power Supply
Memory
VDAC

3. FPGA Parameter name Description Value
Comments regarding choice of parameter value, especially if you had to make assumptions. C1
Die complexity
.29
30,001 to 60,000 Digital MOS gates πT
Temperature coeff.
.71
Linear, temp of 50°C C2
Package Failure Rate
240 Functional Pins, Nonhermatic πE
Environment Factor 2
Ground Fixed πQ
Quality Factor 10
Commercially manufactured component πL
Learning Factor 1
More than 2 years in production λP
Part Failure Rate
Failures/106 hours
MTTF
Hours = Years

4. Microcontroller Parameter name Description Value
Comments regarding choice of parameter value, especially if you had to make assumptions. C1
Die complexity
.28
16 bit MOS gates πT
Temperature coeff.
.71
Linear, temp of 50°C C2
Package Failure Rate
112 Functional Pins, Nonhermatic πE
Environment Factor 2
Ground Fixed πQ
Quality Factor 10
Commercially manufactured component πL
Learning Factor 1
More than 2 years in production λP
Part Failure Rate
Failures/106 hours
MTTF
Hours = Years

5. Power Supply Parameter name Description Value
Comments regarding choice of parameter value, especially if you had to make assumptions. C1
Die complexity
.01
1 to 100 Linear MOS gates πT
Temperature coeff.
.71
Linear, temp of 50°C C2
Package Failure Rate
5 Functional Pins, Nonhermetic πE
Environment Factor 2
Ground Fixed πQ
Quality Factor 10
Commercially manufactured component πL
Learning Factor 1
More than 2 years in production λP
Part Failure Rate
.11194
Failures/106 hours
MTTF
Hours = Years

6. FMECA Functional Blocks FPGA Microcontroller Power Supply
FPGA Peripherals
Microcontroller
Micro Peripherals
Power Supply

7. FPGA

8. FPGA Peripherals

9. FPGA Circuitry Failure No. Failure Mode Possible Causes
Failure Effects
Method of Detection
Criticality
Remarks B1
No clock Signal
Failure of U10 or C14
Device does not functions
Observation
Low B2
Corrupted Data Store
Software, Failure of U3
Unpredictable graphical display
Medium B3
No Video Output
Software, Failure of U5
No display on LCD monitor B4
Code does not load
Failure of U6 B5
No file saved to SD card
Software, Short/Open circuit
No file on SD card

10. Microcontroller

11. Micro Peripherals

12. Microcontroller Circuitry
Failure No.
Failure Mode
Possible Causes
Failure Effects
Method of Detection
Criticality
Remarks C1
Touch Panel does not work
Software, Short/Open circuit
User touch is no recorded
Observation
Medium C2
Color pots do not work
User unable to select colors C3
Pushbuttons do not work
Software, Short/Open circuit, Failure of R3, R4
User unable to save or clear screen
Low C4
LED Driver does not work
Software, Failure of U4
LED does not illuminate C5
SPI communication does not work
Software, Failure of U13
No communication between FPGA and Micro

13. Power Supply

14. Power Supply Circuitry
Failure No.
Failure Mode
Possible Causes
Failure Effects
Method of Detection
Criticality
Remarks A1
5V output = 0V
Failure of U16, C66, D3, C65, L3, External Short
Device does not functions
Observation
Low A2
5V output > 5V
Failure of U16, R36, R32, R25
Possible damage to rest of circuitry
Medium A3
5V output out of tolerance
Failure of C66, C65, R32, R36, U16
Unpredictable operation A4
3.3V output = 0V
Failure of U11, C64, D2, C63, L2, External Short A5
3.3V output > 3V
Failure of U11, R24, R23, R22 A6
3.3V output out of tolerance
Failure of C64, C63, R23, R24, U11 A7
1.25V output = 0V
Failure of U15, C62, C61, D1, L1, External Short A8
1.25V output > 1.25V
Failure of U15, R18 A9
1.25V output out of tolerance
Failure of U15, C62, C61, R18

15. Questions / Discussion