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

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

Power Supply / Battery Charger Schematic

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

MCU Block

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

Accelerometer Schematic

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

Bluetooth Schematic

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

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