Knowledge to Shape Your Future Electric / Gas / Water Information collection, analysis and application MekElekItroniks Design Review Battery Charger Project November

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Agenda System Overview Project Status Mechanical Design Electrical Design Next Steps

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future System Overview Major Components –Plastic Injection Molded Charger Case –Charger Labels –Beryllium Copper Spring Electrical Contacts –Battery Charger PCB –Gang Connection PCB

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future System Overview Functional Requirements User interface is the same as MC-06 with similar front label and instructions Same basic shape/color/material as MC-06 Vertical battery installation Docks with MC-06, using same PCB gang connection and wall power supply Docks 2 Li-Ion battery packs Flashing red LED for charge, solid green charged Cost similar to MC-06

Knowledge to Shape Your Future Electric / Gas / Water Information collection, analysis and application Project Status

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Battery Charger Development Mechanical Design: –Rapid prototype generation, iteration, and testing –SLA generated of Final Design Prototype –Spring contact design prototyped –Injection tooling formulation –Beginning Final Design Documentation Electrical Design: –Schematic Design –EAGLE Layout –Voltage Regulation Prototype –MAX1737 Design, Prototype –Beginning Final Design Documentation

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Project Costing Injection Molded Charger Case –Using cost estimate from MC-06 –Top Plate - $2.97/unit –Bottom Plate - $1.77/unit Electrical Spring Contacts –One time tool charge of $9,000 - $11,000 –$.08 - $.12 per spring –6 springs/unit yields a cost of about $2.92/unit Charger PCB / Electrical Components –Cost of $26.86/unit for all electrical components Total Cost –Materials - $35.66 –Assembly - $3.83 –Overhead and Profit - $17.73 –Total Unit Price - $57.22

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Battery Charger Schedule 11/04 09/04 01/0512/05 10/04 02/0504/0503/05 Mech Design Product Testing PCB Layout Elect Design Inj. Tooling Design Doc. Build Tooling 05/05 Manufacturing 20 Prototypes Piece/Part Design

Knowledge to Shape Your Future Electric / Gas / Water Information collection, analysis and application MECHANICAL DESIGN REVIEW Rory Olson James Franklin

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Design Overview Highlights –Updated Design Battery Alignment Slots Electrical Spring Contacts –Accommodates Ergonomic Battery Pack –Exterior similar to MC-06 Features –Curved Battery Pocket –Drain / Mounting Boss –Beryllium Copper Electrical Contacts –Contact Alignment using PCB Design

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Design Overview Battery Charger Top Plate –Curved Battery Pocket Designed around Battery Pack shape –Three Contacts Slots Contact Alignment Fins –Prevents Shorts –Pass Core Contact Slots No need for Expensive Slide Mechanism –Drain Boss Drain Foreign Materials Adds Surface Mounting Option

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Design Overview Battery Charger Bottom Plate –Similar to Previous Design –Removed Interior Support Flanges –Drain Boss Holes Moved small Label on Bottom

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Design Overview Printed Circuit Board –Single Layer PCB –Sandwiched between Top and Bottom Plates –Beryllium Copper Spring Contacts Mounted underneath of PCB with PEM Nuts and Mounting Screws –PCB Alignment Slots Spacing Prevents Shorts –Battery Pocket Cut-outs

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Design Overview Beryllium Copper Electrical Spring Contacts –Beryllium Copper chosen for its formability, high electrical conductivity, high fatigue strength, and corrosion resistance –Used deflection model to ensure 1/2 lb contact load per contact –Optimized design using infinite fatigue life model –Slope face to accommodate sharp battery edge –Mounted directly to PCB with threaded PEM inserts

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Design Overview Basic Assembly –Spring contacts mounted to PCB through PEM nuts using screws –Board captured between case halves –Two halves screwed together with six mounting screws –Instruction label place on label surface –Rubber feet attached to bottom plate using adhesive –Units connected together using previous gang connection PCB

Knowledge to Shape Your Future Electric / Gas / Water Information collection, analysis and application Electrical Design Overview Joe Cote Lee Solum

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Design Overview Highlights –Design new charging circuit Accommodate one cell Li+ battery pack Incorporate original gang connectors Maintain original display characteristics –Meet FCC class A requirements –Conform to PCB real-estate Features –Safely and accurately charge battery –Maintain interconnectivity with MC-06 –Maximize efficiency while minimizing cost

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Design Overview Charging IC Selection –Logic vs. Microcontroller Pros and cons –Designed for Li+ batteries Accurate charging capabilities Integrated safety features –Incorporated Charge Status Voltage detection Current detection –Maintain Charge Reverse leakage protection

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Design Overview Voltage Regulation and Protection –Input Voltage Maintain constant voltage –Noise Prevention DC plug protection Emissions –ESD Incorporated protection

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Design Overview Alternate Design –MAX1737 Incorporated Design Expandability –Pros Size Component count Greater protection –Cons Cost

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Design Overview Layout –Software EAGLE –Component Placement –Routing –Footprints OrCad –Itron compatibility –Conflicts Importing Cross Compatibility

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Next Steps Mechanical Design: –Design Documentation / Fabrication Drawings –Formulate Plastic Injection Molding Tooling –Build Plastic Injection Tooling –Create Mechanical Prototypes –Assemble Prototypes –Product Testing Electrical Design: –Design Documentation / Schematics –Create Electrical Prototypes –Product Testing

Electric / Gas / Water Information collection, analysis and application Knowledge to Shape Your Future Q & A QUESTIONS