ECE 477 Design Review Team 8(SLOW)  Spring 2006

Outline Project overviewProject overview Project-specific success criteriaProject-specific success criteria Block diagramBlock diagram Component selection rationaleComponent selection rationale Packaging designPackaging design Schematic and theory of operationSchematic and theory of operation PCB layoutPCB layout Software design/development statusSoftware design/development status Project completion timelineProject completion timeline Questions / discussionQuestions / discussion

Project Overview Designing an LED panel by cascading 10 5x7 LED dot matrices.Designing an LED panel by cascading 10 5x7 LED dot matrices. A built in embedded server on the microcontroller to edit/display text messages on the LED panel via a website.A built in embedded server on the microcontroller to edit/display text messages on the LED panel via a website. Scrolling feature to display long text messages.Scrolling feature to display long text messages. Allows users to display the outdoor temperature using a temperature sensor.Allows users to display the outdoor temperature using a temperature sensor. Display current time using a highly accurate internal clock.Display current time using a highly accurate internal clock.

Project-Specific Success Criteria Ability to display ASCII character strings on an LED matrix.Ability to display ASCII character strings on an LED matrix. Ability to save messages and configuration data in non-volatile memory.Ability to save messages and configuration data in non-volatile memory. Ability to measure and display the outdoor temperature.Ability to measure and display the outdoor temperature. Ability to display the current time (based on highly accurate internal clock).Ability to display the current time (based on highly accurate internal clock). Ability to configure display and edit messages via an embedded server.Ability to configure display and edit messages via an embedded server.

SLOW Block Diagram

Component Selection Rationale Microcontroller : Must have a timer module for the clock, a ATD port for the temperature sensor, built in ethernet controller, PWM module. Choices : Choices : Freescale MC9S12NE64CPV -80 pin package, 38 I/O pins and 10 input only -64K of FLASH memory -ATD ports -Timer Module -A IEEE compliant ethernet controller Rabbit RCM I/O pins -Built in Ethernet Controller -512K of FLASH memory We decided with the MC9S12NE64CPV as it has a low cost, easily attainable and has a enough number of input output pins. Also, the MC9S12NE64CPV has good documentation as compared to the Rabbit microcontroller.

Component Selection Rationale LED Driver Toshiba TB62708 with a 16 bit shift register and latching ability -Low cost -Programmable Output current from 5mA to 90mA -Current sourcing device We required a 12 bit shift register for our design but we could only find current sinking ones. ULN2003A Darlington Array -16 Bit package -Sinks upto 500mA of current( our sink current came upto 105mA) -Recommended by our TA Brian as used by him for one of his LED projects RJ45 Jack -Recommended by the microcontroller data sheet

Packaging Design Considerations : LED’s panel is big enough and can be seen from a distance of up to 30 feet.LED’s panel is big enough and can be seen from a distance of up to 30 feet. Aluminum CaseAluminum Case Weight estimation : around 3.4 lbs and mountable on a wall.Weight estimation : around 3.4 lbs and mountable on a wall. Dimension is 17” x 4” x 3”Dimension is 17” x 4” x 3”

Packaging Design – 3D view

Packaging Design – Front

Packaging Design - Bottom

Schematic/Theory of Operation

Total Parts : 88Total Parts : Capacitors 2 Diodes 25 Resistors 3 Switches 1 crystal 10 LED drivers 10 Darlington transistors 2 Inductors 10 LED displays 1 Microcontroller 2 Power Regulators 1 RJ-45 1 BDM 1 Header 1 Temperature Sensor 1 12V Power Adapter Schematic/Theory of Operation

PCB Layout – Whole Layout

PCB Layout – Top Layer

PCB Layout – Bottom Layer

PCB Layout - Microcontroller

PCB Layout – Power

PCB Layout – Shift Register and transistors

PCB Layout – RJ45

Software Design/Development Status –All programming and decoding will be done on the Microcontroller – Even without the PCB, MC9S12NE64 Development board can be used to write code and test our components. – LED matrices are driven by column therefore making it possible to control text scrolling.

Project Completion Timeline Week 8 (This week) – Finalize PCB / Design ReviewWeek 8 (This week) – Finalize PCB / Design Review Week 9 – Start Software Development / Final PCB ModificationWeek 9 – Start Software Development / Final PCB Modification Week 10 – Testing hardware / Continue Software DevelopmentWeek 10 – Testing hardware / Continue Software Development Week 11 – Continue Software Development / Testing PCB FunctionalityWeek 11 – Continue Software Development / Testing PCB Functionality Week 12 – Finalize Software / DebuggingWeek 12 – Finalize Software / Debugging Week 13 – Packaging / Testing / DebuggingWeek 13 – Packaging / Testing / Debugging Week 14 – Final TweakingWeek 14 – Final Tweaking Week 15 – Documentation / Prepare for Final PresentationWeek 15 – Documentation / Prepare for Final Presentation Week 16 – Final PresentationWeek 16 – Final Presentation

Questions / Discussion