Design Considerations for Embedded Designs
YOU’RE IN FOR A TREAT
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A LITTLE BIT ABOUT US
Epsilon 5 Engineering (E5E) was created as a
spin-off venture from the University of New
Brunswick’s world renowned Institute of
Biomedical Engineering (IBME). We are a
research and development company whose
personnel has been involved in numerous stateof-the-art projects (ACOA AIFs, US DARPA
Revolutionizing Prosthetics).
UNB’s
Institute
of
Biomedical
Engineering
LEARN MORE AT:
WWW.EPSILON5ENGINEERING.COM
QUALIFIED PROFESSIONALS
• Mechatronic Applications
• Measurements
• Embedded Systems
• PCB Design
• Product Assembly
• Firmware Programming
• Low Power Systems
• Biomedical Instrumentation
• Analog Design
How do I start planning a microcontroller-based design?
Improves time estimates for project completion
Ensures project’s feasibility
Prevents the addition of new features during the
project design (a.k.a. feature creep)
How do I start planning a microcontroller-based design?
Improves time estimates for project completion
Ensures project’s feasibility
Prevents
the
addition
of
new
features
during
the
High level scope of the project
project design (a.k.a. feature creep)
Lock in commitment
How do I start planning a microcontroller-based design?
High level scope of the project
Lock in commitment
Analyze, design, and document algorithms/processes
Identify and devise predictable and robust operation
Do I need them?
What should I use?
Other factors?
What kind of on-chip peripherals are available?
Analog to Digital converters
Communication modules
(I2C, SPI, UART, CAN, USB)
Output comparator (PWM, Digital Pulse)
So many choices… How do I choose?
So many choices… How do I choose?
May cut down on code size
Decreases complexity
Reduces number of pins used
...
Power Budget
Battery or mains powered?
Low power vs cost vs size
Device usage scenarios
Battery capacity, physical size and chemistry
Temperature effects
Supply voltage effect
Tips for Power Reduction
Sleep, Idle, Doze, etc
Peripheral availability
Clock sources and clock switching
Built-in peripherals
External peripherals
I/O pins and pull-ups
Code Optimization for Power Reduction
Power vs clock frequency (P=CV2F)
Impact on peripheral power
Transmission rates
Bit shifting vs multiplying/dividing
Interrupts
Instruction cycle count
Component Selection
You get what you pay for
Parametric Search
Think long term
Minimum quantity
Availability
Use customer reference (or similar)
Include all details (package, tolerance, temp, etc.)
“Missing or incomplete documentation is the lead cause of production
delays, defects and cost overruns” (www.bunniestudios.com)
Schematic/PCB Design
Proper/consistent parameters for all parts
Andrew Huang (www.bunniestudios.com)
Single Sided? (Soldermask)
Test points
Size – How small is too small?
Manufacturer (4x4” board):
APCircuits
PCB Pool
Price
$167
$71.65($125.77)
Delivery Time Ships in 3 days 8 days (4 days)
with overnight
Notes
16 sq inch min
OSH Park
$80
2-3 weeks
$5 sq inch
Case
Import existing PCB shape
Import case to define board shape
Datasheet drawings
PCB shape first to meet layout requirements
Use CircuitWorks or Desktop EDA if possible
Import PCB into ECAD as part of assembly to
create case shape
HAVE A WONDERFUL DAY