1. Dong-Han Ryu Yukeun Sim Shiv Biddanda Po-Cheng (Robert) Wang
Reliability/Safety Analysis
Dong-Han Ryu
Yukeun Sim
Shiv Biddanda
Po-Cheng (Robert) Wang

2. Criticality Levels High Medium Low
Failure of one block and related subsystem
Damage to PCB
Medium
Damage to single block
Does not affect working operation of other blocks
Low
No damage to components
Wiring, Software Design

3. Power Supply / Battery Charger Schematic

4. FMECA - Power Supply/Charging
Failure No.
Failure Mode
Possible Causes
Failure Effects
Method of Detection
Criticality
Remarks 1
Battery Charger IC Failure
Supply voltage too high/low
No charging
Bad charging rates
LED
High
Affects operation of entire PCB. 2
Voltage regulator IC Failure
Over/undercharge
Charging rate too high
Damage to battery
Leakage
Explosion
Observation
Battery very sensitive to charging characteristics and may explode if mis-handled

5. MCU Block

6. FMECA – MCU Block 1 Dead pic18f4550 – unresponsive
Failure No.
Failure Mode
Possible Causes
Failure
Effects
Method of Detection
Criticality 1
Dead
pic18f4550 –
unresponsive
Failure of power system
Short on bypass capacitors
Failure of crystal
Non-programmable
Failure of
system
Observation
High

7. Accelerometer Schematic

8. FMECA - Accelerometer 1 No output on port Pins Bypass caps C1-C3
Failure No.
Failure Mode
Possible Causes
Failure Effects
Method of Detection
Criticality 1 No
output on
port
Pins
Bypass caps C1-C3
shorted
Open line
between glove and
main PCB
IC Damaged due to extremely quick movement, dropping IC
No ATD input
Observation
Medium 2
Noisy
Failure of op-amps
Failure of passive components
Incorrect cursor movements on PC
Low

9. Bluetooth Schematic

10. FMECA - Bluetooth Module
Failure No.
Failure Mode
Possible Causes
Failure Effects
Method of Detection
Criticality 1
Incorrect data on
host PC
Retransmission of
data
Error in packet construction
Unpredictable
cursor movements
Observation
Low 2
No data
UART Tx error
No Bluetooth handshake between host PC and radio No
cursor movement

11. Questions?