Team MUX

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Team MUX

• Adam Burton Mark Colombo
• David Moore Daniel Toler

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Introduction

• Overview
• (3) 16 Bit Master-Slave Rising edge registers
  using transmission gates
• ALU comprised of 5 functional blocks
• Adder/Subtractor
• And
• Or
• Shift
• Multiplier

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Team MUX- ALU Block
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Adder/Subtractor Bitslice

• In our Adder/Subtractor we had two bit slices
  with different inverting stages. This was so we
  could take advantage of the inversion property to
  cut down on the number of inverters in the carry
  path.

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Shifter Bitslice

• We used passgate logic because the reduced
  output swing was not an issue, and we could save
  area.

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Functionality Plots
Pass c2c1c0001 A00gt1 Out00gt1
CLK
A0
A0
Out0
Out0
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Functionality Plots
AND C2c1c0110 A01gt0 B00 Out01gt0
CLK
Out0
A0
Out0
A0
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Functionality Plots
SUB c2c1c0011 A01 B01 Out00
CLK
A0,B0
A0,B0
Out0
Out0
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Innovation

• Sizing Strategy
• What to size
• How to size it
• Design Trade-Offs
• Arbitrary Function 16 bit multiplier

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Sizing

• Not on Critical Path ? Sized to conserve area
• On Critical Path ? Sized for Delay
• Attempted Logical Effort Calculations
• Result Tapered Path for reduced delay
• Optimized further through simulation
• Buffers between registers and ALU

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Trade-Offs

• Considered Carry Look-ahead Adder
• Additional area and power
• Small benefit to delay
• Supply Voltage
• Higher ? Better Delay, More Power
• Lower ? Worse Delay, Less Power
• Decided on Delay due to being squared in metric,
  used 5V

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Innovation in Multiplier

• To produce a 16-bit output, need 8-bit multiplier
• Team MUX Multiplier is 16 bits
• Despite limited output width, offers more
  flexibility

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Multiplier Attributes

• The multiplier is a basic array-based multiplier.
• Delay through the multiplier
• Power consumption of the multiplier

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Results

• Worst case delay analyzed
• 0x7FFF 0x0001 
• Caused all bits to flip
• Period 7ns
• Frequency 143 MHz

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Results

• Area measurement
• Counted up widths
• Excluded buffers and multiplier
• Width 4.211510-3 m

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Results

• Energy calculation
• Cycle through all functions with alternating
  input
• Integrated instantaneous power over period of
  operation
• Energy 2.342610-9 J

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Results

• Final Metric
• D2AE
• Metric 4.84610-28 s2mJ

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Conclusion

• Meets or exceeds all specifications
• Implements all functions
• Low metric value
• Multiplier is a valuable, common function

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Questions?