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Lucas-Lehmer Primality TesterPresentation 6March 1st 2006

Team: W-4

Nathan Stohs W4-1

Brian Johnson W4-2

Joe Hurley W4-3

Marques Johnson W4-4

Design Manager:

Prateek Goenka

Overall Objective: Modular Arithmetic unit with a creative use

This is my presentation, there are others like it but this one is mine

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Status• Finished

– Project Chosen– C simulations– Behavioral Verilog– Structural Verilog– Revised Floor Plan– Schematics ( 98%)

• In Progress– Top Level Simulations– Layout– Layout Simulations

• To Do– Continue Layout– Layout Simulations– Pathmill Simulation on Top Level

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Design Decisions• Optimization

– Got rid of universal Shifter– Implemented Shifter_Left Shifter_Right– Stressed special cases over universal parts– Cut out 4,000 transistors

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Transistor Counts (Old)Module Transistor Count

FSM 300

Mod Calc 2440

Counter 1656

Mod Multiply 15302

Mod_Add

Shifters

Registers 1848

Compare for zero 92

Total 21638

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Transistor Counts (New)Module Transistor Count

Count 2,664

Mod_Multiply 11,120

Mod_Add 1282

Partial Products 8,676

Counter 266

Dff_re (16) 896

Sub_16 704

Compare 36

Mod_P 1,280

Top Level Flops 896

FSM 700

Total 17,400

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Power ConsumptionModule Power

Count 53.81 uW

Mod_Multiply ?

Mod_Add 128.8 uW

Partial Products 368 uW

Counter 36.77 uW

Dff_re (16) 260 uW

Compare 149.2 pW

Mod_P 397.6 uW

Top Level Flops 39.6 uW

FSM ?

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Shift_Left

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9

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Shift_Right

11

12

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Mod_P

14

15

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Partial Product

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18

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Pathmill Results

• Shift_Left = .610 ns

• Shift_Right = .610 ns

• Mod_P = .610 ns

• Mod_Add = 8.993 ns

• Partial_Products = 5.135 ns

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Initial Layout

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More Layout

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Block Area Estimates (Old)

Module Area (μm2)

FSM 900

Mod Calc 3500

Counter 6000

Mod Multiply 75000

Registers 3000

Compare for zero 300

Total 88300

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Block Area Estimates (Updated)

Module Area (μm2)

Count 13,200

Mod_Mult 54,500

Sub_16 3,500

Compare 200

Mod_P 6,500

Top Level Flops 4,400

FSM 3,500

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Updated Floorplan

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What’s Next

• Continue Layout

• Pathmill Simulations for Top Level

• Simulate Layout

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Questions?