Random Number Generator Dmitriy Solmonov W1-1 David Levitt W1-2 Jesse Guss W1-3 Sirisha Pillalamarri W1-4 Matt Russo W1-5 Design Manager – Thiago Hersan February 22, 2006 Top Level Integration Project Objective: Create a Cryptologically Secure Pseudo-Random Number Generator

Agenda Status Design Decisions Timing Constraints Timing Analysis Power Analysis Registers

Status Completed C implementation Architecture Behavioral Design and Simulation Gate-Level Design and Simulation Preliminary Floorplan In Progress  Schematic Design and Simulation (90% Done)  Layout Unfinished Extraction, LVS, post-layout simulation

Design Decisions Adder, FSM and SRAM Design Finalized Register Design Finalized –Counter Regs Based on JKFF –Data Regs Based on HLFF

Timing Constraints To understand our timing constraints, we have to go back and look our pipeline Stage 1 0) M1=M[i+32]A1=barrel(A) 1) X=M[i]A=A1+M1 2) M3=M[X]A=A1+M1 C1=(X==i-1) 3) Y1=A + (C1) ? Y : M3 4) Y1=A + (C1) ? Y : M3 Stage 2 0) Y=B+Y1YL=B[13:0]+Y1[13:0] 1) Y=B+Y1M4=M[Y[13:8]] C2=(I==Y[13:8]) 2) B=X+(C2) ? Y : M4 3) B=X+(C2) ? Y : M4M[i]=Y 4) R[i]=B

What does this mean? Since we have allotted the adder two ticks, the FSM one tick, and the SRAM half a tick… The adder’s propagation delay SHOULD be double that of the FSM, which has a propagation delay that SHOULD be double that of the SRAM

Timing Analysis - Adder Since our adder is so complicated we were unsure how to locate the critical path on the schematic by hand We found the critical path of the adder to be from the B[4] pin to the S[31] pin using Pathmill

Timing Analysis - Adder Total Prop Delay: 1.44ns

Timing Analysis - FSM Total Prop Delay: 816ps

Timing Analysis - SRAM The SRAM timing analysis had to happen in two parts. A test row and a test column were constructed to isolate different components of the SRAM

Timing Analysis – SRAM Row Row Prop Delay: 445ps

Timing Analysis – SRAM Column Column Prop Delay: 290ps Total Prop Delay: 735ps

Putting it All Together ComponentTransistor CountAreaProp Delay Power Adders (4x)5856 (1464 each) 2700um 2 (675um 2 ea.) 1.44ns888uW FSM194100um 2 826ps46uW SRAM17736 (M=10458 R=7278) 8000um 2 735psW: 510uW R: 190uW Datapath w/o Adders um 2 Total um 2 TBD

Registers Using JKFF for Counter Regs

Registers Using HLFF for Data Regs

Timing Analysis – Registers JKFF –Rise time = 200p –Fall time = 200p HLFF w/ Clear w/ 20fF load –Rise time = 140ps –Fall time = 70ps HLFF w/ Load and Clear w/ 20fF load –Rise time = 200p –Fall time = 170p

Thanks! Any Questions?