1. Team # 10 Milestone # 3 –System-Level Design Review Faculty Advisor/Reviewers: Dr. Michael Frank Dr. Bing Kwan Dr. Rajendra Arora Team Members: Monica Pereira Monique Peregrina Liang Liufu Ifedayo Ogundana Sponsored by: Albert Daci

2. The purpose of this project is to design an original cap that implements electroluminescent technology. This cap will consist of a panel with flashing capabilities and with a hidden internal circuit. Each cap will implement a switch with three states (turn on, flash, turn off) and be provided with an internal circuit with water resistant capabilities. In addition, the cap will come with a micro-USB charger hidden underneath the bill of the cap. 2 Monica Pereira

3. 3

4. Front View Internal View 4 Monica Pereira

5. Fitted baseball cap LiPo rechargeable battery Battery charger 10cm x 10cm EL panel 3V DC battery inverter IC chip Liquid Encapsulating epoxy resin Reference No. DescriptionComponent fulfilling this requirement REQN-001 The design must be able to light on, blink and turn of. Timing IC REQF-002 Use slim batteries that maximize the prototype efficiency Li-Po rechargeable battery & battery charger REQN-004 REQN-006 Components will be water resistant Design will withstand common wear and tear. Epoxy resin encapsulating material CAP-001 REQF-004 Panel must be able to turn on continuously, blink and turn off. A miniature button switch should be implemented in the bill to turn on/flash/turn off the EL logo. Blinking will be fulfilled through the timing IC The three operating modes will be operated through the single pole, triple-throw switch 5 Monica Pereira

6. The following components have remained the same: ItemSpecifications Nominal Capacity 1000 mAh Nominal Voltage3.7V Standard Discharge Current 0.2A Max Discharge Current 2.0 A Cell Voltage3.7-3.9 V WeightApprox.: 20g 6 Monica Pereira

7. ParameterValue Regulated output voltage4.20 V Temperature range-40ºC to 85ºC The LiPo Charger Basic uses a Microchip MCP73831T- 2ACI/OT charge management controller to charge 3.7V Li-Po batteries at a rate of 500mA per hour. The board incorporates a charging circuit, status LED, connector for your battery (JST type), and USB connector. A small mounting hole allows this charger to be embedded into a project easily. 7 Monica Pereira

8. Specifications Specifications Type: 555 type, Timer/Oscillator (Single) Supply Voltage: 2 V ~ 18 V Current: 60µA Operating Temperature: 0ºC to 70ºC Max Frequency: 1 MHz 8 Monica Pereira

9. ColorBlack Cure Cycle24 h Dielectric Strength19.36 kV/mL Pot Life60 minutes Reasons it was selected: Excellent electrical insulation properties Good storage stability Supports high temperatures 9 Monica Pereira

10. 10

11. SpecificationsEL panel Glow size10cm X 10cm (3.95" x 3.95") Panel lifetime Greater than 25000 hours Operating voltage60-250V AC Operating frequency 50-5000 Hz Current Draw0.14mA/cm 2 (max) @ 110V / 400Hz Initial Brightness75 cd/m 2 Operating Temperature -50 C / 65 C Panel Capacitance45nF EL Panels from Surelight.com (Previous vendor was Adafruit ) 11 Monica Pereira

12. Weight2.2g Frequency2500Hz Power Supply Required 3V or 1.5V DC 3V ELI-IMC Battery Inverter Design our own inverter instead 12 Monica Pereira

13. 13

14. 14 Liang Liufu

15. 15 Liang Liufu

16. Requirements: Input uses 3.7VDC Output 110VAC Output Current: >14mA Output Frequency: 400Hz 16 Liang Liufu

17. Wien-Bridge Oscillator Requirements 3.7V input 400Hz output 20mA output 17 Liang Liufu

18. Output: 4.7Vp-p 27.6mAp-p 395Hz 18 Liang Liufu

19. Requirements: Amplify oscillator signal to achieve 110VAC Maintain 400Hz Output current of 14mAp-p 19 Liang Liufu

20. 20 113VACp-p output 12.1mAp-p output 400Hz output Liang Liufu

21. 21 Liang Liufu

22. 22 110VACp-p Output 14.1mAp-p Output 395Hz Liang Liufu

23. In charge of controlling the blink pattern Will allow the logo to flash every second Uses a 555 Timing IC Specifications: Power consumption: 15 mW Input voltage: 3.7V Output Voltage: 3.7V Frequency: 1 Hz Monique Peregrina

26. FULL CIRCUIT SIMULATION ON BLINK STATE 26 Monique Peregrina

28. Battery Life Decreased Probability: Moderate Consequence: Moderate Strategy El Panel Not Bright Enough Probability: Low Consequence: Severe Strategy Timing IC Does Not Supply Enough Power Probability: Low Consequence: Moderate Strategy 28 Monique Peregrina Disconnected Wires Probability: Moderate Consequence: Devastating Strategy Moisture near Electronics Probability: Very High Consequence: Catastrophic Strategy Overheating Probability: Moderate Consequence: Moderate Strategy

29. Tasks Assignment Probability- high; Consequences- moderate Strategy – Proper communication amongst members. Design dependencies Probability- low; Consequences- moderate; Strategy- to be set aside for help from advisor Personal complications Probability- very low; Consequences – severe; Strategy – re-planning of task division Individual productivity Probability- high; Consequences – severe; Strategy- constant evaluation of individual progress 29 Ifedayo Ogundana

30. More components may be needed Probability – moderate Consequence – minor Strategy – some funds are reserved Damaging the timer IC and/or the inverter Probability – low Consequence – severe Strategy – funds are reserved for purchase of extra major components Unaccounted-for-costs Probability- low Consequence - moderate, Strategy – low price components are purchased and expenses are cut down Budget limitations Probability – low Consequence – moderate Strategy – component parts are ordered to together to reduce cost of shipping. 30 Ifedayo Ogundana

31. CURRENT EXPENSES (CUSTOM INVERTER) 31 Ifedayo Ogundana Expenses Subtotal = $413.89 → $650.00 - $413.89 = $236.11 (Under budget)

32. CURRENT EXPENSES (OFF-THE-SHELF INVERTER) For off-the-shelf inverter: Expenses Subtotal = $446.34 → $650.00 - $446.34 = $203.66 (Under budget) 32 Ifedayo Ogundana

33. EL Cap Budget Updated Per-Unit Budget 33 Ifedayo Ogundana

34. CURRENT EL CAP REPLICATION BUDGET (CUSTOM INVERTER) 34 Ifedayo Ogundana

35. 35 Monica Pereira

36. 36 Monica Pereira

37. EXTRA SLIDES FOR REFERENCE 37

38. 38 ItemTest MethodsPerformance Over charge At 20±5°C charging batteries with constant current 3A to voltage 4.8V, then with constant voltage 4.8V till current decline to 0. Stop test until batteries temperature is 10 degrees lower than max temperature. No explosion or fire Over dischargeAt 20±5°C discharge battery with 0.2A continuously 12.5h.No explosion or fire Short-circuitAt 20±5°C connect batteries’ anode and cathode by wire which impedance less than 50mΩ, keep 6 h No explosion or fire Thermal shock Put the battery in the oven. The temperature of the oven is to be raised at 5±10 degrees per minute to a temperature of 130degrees and remain inside the oven 60 minutes. No explosion or fire

39. 39 Cautions of charge & discharge Charge Charging current should be lower than values that recommend below. Higher current and voltage charging may cause damage to cell electrical, mechanical, safety performance and could lead heat generation or leakage. Batteries charger should charging with constant current and constant voltage mode Charging current should be lower than (or equal to ) 1A Charging voltage must be lower than 4.25V Discharge Discharging current must be lower than (or equal to )2A Discharging voltage must not be lower than 2.75V. Over-discharge It should be noted that the cell would be at an over-discharge state by its self-discharge. In order to prevent over-discharge, the cell shall be charged periodically to keeping voltage between 3.6-3.9V.

40. 40 Supply Current - Current in mA/cm2 versus supply voltage: As the supply current is increased for the EL panel, the supply voltage also increases. Figure 17 Supply Voltage vs Brightness

41. 41 Brightness Vs Time with time. Unlike most other lighting which can critically fail, EL Panel brightness decreases with time. The following factors have an impact on lifetime: Higher Voltage Higher Frequency DC Supply High Ambient Humidity High Ambient Temperature Brightness can be increased by using a higher voltage or higher frequency. Higher voltage slightly decreases life time, but is preferred if higher supply current can be accepted.

42. 42 EL Panels emit light from 50VAC and increase in brightness with higher voltage up to 200VAC. The frequency should be over 50Hz. Brightness increases with higher frequency up to 1000Hz. However, it is recommended that frequencies in the range of 400- 600Hz and voltages of no greater than 160VAC are used, otherwise the panel life will rapidly deteriorate.

43. 43