V i t a l i s ECE Spring 2013 TEAM 13 Presenter: Yi Shen Wireless Biometric Sensor Team Members: Aakash Lamba Di Mo Shantanu Joshi Yi Shen Reliability and Safety Analysis

Prototype of a portable wireless biometric sensor Battery-powered device with fuel gauge Mounted on the wrist Monitor vital signs such as pulse rate, SpO 2 and skin temperature Transmit the information via Wi-Fi for remote web access NFC chip allows immediate access Accelerometer on the shoulder for fall detection Manual and automatic alarm system. Project Overview

Block Diagram

Definition of Criticality Levels

1.Microcontroller: Atmel – ATmega Light-To-Frequency Converters: TAOS – TSL230RD 3.Charger/Booster: Charger – MC73831 Boost Converter – TPS61200 Components Failure Analysis

Microcontroller: Atmel – ATmega 1284 MOS digital microprocessor devices (Mil-Hdbk-217F) ParameterDescriptionValueComment Die complexity failure rate bit microcontroller Temperature factor0.98Operating at 85 °C Package failure rate pin SMT Environment factor4.0Ground Mobile Quality factor10Other Commercial Level Learning factor1 > 2 yrs in production Reliability2.212 MTTFEntire Design years

Light-To-Frequency Converters: TAOS – TSL230RD Linear Gate / Logic Array (Mil-Hdbk-217F) ParameterDescriptionValueComment Die complexity failure rate0.01<100 transistors Temperature factor7.0Operating at 30 °C Package failure rate pin SMT Environment factor4.0Ground Mobile Quality factor10Other Commercial Level Learning factor1 > 2 yrs in production Reliability0.836 MTTFEntire Design years

Charger – MC73831 Linear Gate / Logic Array (Mil-Hdbk-217F) ParameterDescriptionValueComment Die complexity failure rate0.01<100 transistors Temperature factor7.0Operating at 85 °C Package failure rate pin SMT Environment factor4.0Ground Mobile Quality factor10Other Commercial Level Learning factor1 > 2 yrs in production Reliability0.78 MTTFEntire Design years

Boost Converter – TPS61200 Linear Gate / Logic Array (Mil-Hdbk-217F) ParameterDescriptionValueComment Die complexity failure rate0.01<100 transistors Temperature factor7.0Operating at 85 °C Package failure rate pin QFN Environment factor4.0Ground Mobile Quality factor10Other Commercial Level Learning factor1 > 2 yrs in production Reliability0.870 MTTFEntire Design years

Schematic: Section Breakdown Microcontroller Power and Battery Management Sensors External Interfaces

FMECA Chart Microcontroller: Atmel – ATmega 1284 Failure No. Failure ModePossible CausesFailure EffectsDetection MethodCriticality A1Failure of UARTWrong connections for TX/RX Wi-Fi and OLED won’t communicate with micro properly InspectionHigh A2Over-currentDecoupling Capacitors are shorted Micro doesn’t function any more Inspection and ICD3 debugger High A3Failure of I2CPull-up resistors are shorted Unable to retrieve data from temp sensor and fuel gauge InspectionMedium A4Failure of GPIOBad wire connectionsUnable to detect falling position/ control LEDs for SpO2 Sensors InspectionMedium

Failure No. Failure ModePossible CausesFailure EffectsDetection MethodCriticality B1Failure to operateBad solder for GND and Vcc Micro won’t receive any data about patient pulse and blood oxygen concentration information InspectionMedium FMECA Chart Light-To-Frequency Converters: TAOS – TSL230RD

Failure No. Failure ModePossible CausesFailure EffectsDetection MethodCriticality C1OverheatToo much currentDamage BatteryInspectionhigh FMECA Chart Charger – MC73831

Failure No. Failure ModePossible CausesFailure EffectsDetection MethodCriticality D1Over-heatToo much currentOutput less than 5V, OLED screen won’t be powered on ObservationMedium FMECA Chart Boost Converter – TPS61200

Questions?