1. 1 A Low-Power True Random Number Generator using Random Telegraph Noise of Single Oxide-Traps Class presentation of advanced VLSI design University of tehran, FALL 2006 Represented by Mehdi Mohamadi Adopted from ISSCC 2006

2. 2 What’s Random Number ?

3. 3 Produce and sample noise signal Pseudo Randomn Number Generator (PRNG) Random Number=f ( seed) True Random Number Generator (TRNG) Random Number = f ( noise)

4. 4 Pseudo Random Middle square method seed= 345674 seed ² = 119490514276 New seed = 490514 problem : if seed=0 => generator freeze Use by ENIAC ( 1946-1995)

5. 5 module von_neumann(clk,reset,out); output [9:0] out; input clk,reset; reg [19:0] a; reg [9:0] out; always @(posedge clk) begin if (reset) out=10'b1001011010; else begin a=out*out; out=a[14:5]; end endmodule Synthesis on Stratix

6. 6 Pseudo Random 6 bit pseudo random number generator

7. 7 Pseudo Random : complex hardware,Low frequency,unreliable data => week security Why pseudo ??? When we can flip a coin!!

8. 8 True Random Chaos theory Thermal Noise But Noise?

9. 9 Noise Effect Does Differential comparator help us ?

10. 10 Intel RNG

11. 11 What’s new in this design? Low power and Area consumption Noise tolerant Voltage variation tolerant ( suitable for security controller) => introduce new field oxide trap

12. 12 Large noise amplitudes (~1mV) for small area devices White noise in certain frequency bands … but strong fluctuations in the low-frequency noise Noise of small area MOSFETs

13. 13 But is probability of ‘1’ =probability of ‘0’ ?? => Von Neumann algorithm CLK + - V ref. Random numbers Decoder + - Quality Check HPF von Neumann Algorithm: 00 no data 01 ‘1’ 10 ‘0’ 11 no data 101101 V random numbers V ref. t CLK V noise

14. 14 TRNG Schematics: Noise Source and Amplifier

15. 15 TRNG Schematics: Noise Source and Amplifier 10 times repeated Auto calibration procedure determines best fitted noise source

16. 16 TRNG Schematics: Filter Low accuracy of these devices is no problem here (filter corner frequency has no fixed value, but needs to be ~ 5- 20kHz) C 31 C 32 noise 1 noise 2 V ref_comp R 32 R 31 f_noise 1 f_noise 2 V bias2 V bias3

17. 17 TRNG Schematics: Comparator Comparator is optimized for low mismatch and low hysteresis T7T7 T6T6 CLK f_noise 1 f_noise 2 T9T9 T8T8 T 11 T 10 T 13 T 12 T5T5 T4T4 out 1 out 2

18. 18 TRNG – Measured Output Data Raw data rates of up to 5MHz possible However correlation reduces randomness -> necessity to apply post processing (v. Neumann algorithm)

19. 19 TRNG Basic Electrical Performance Area (in 0.12µm CMOS):0.009 mm² (analog part only) Power consumption:< 20µW + 30µW/MHz *f clock PSRR @500kHz (simulated):~ 30dB CMRR @500kHz (simulated):~ 30dB Raw data rate (typical / max.):500kHz / 5MHz

20. 20 Random Number Data rate 4 different noise sources on the same die

21. 21 Random Numbers - Mean Value

22. 22 Random Numbers - Mean Value 4 different noise sources on the same die

23. 23 REFERENCES [1] Ralf Brederlow1, Ramesh Prakash 2, Christian Paulus3,Roland Thewes1 “A Low-Power True Random Number Generator using Random Telegraph Noise of Single Oxide-Traps “ ISSCC 2006 [2] B. Jun, P. Kocher, “The Intel Random Number Generator,” white paper, http://www.cryptography.com/resources/whitepapers/IntelRNG.pdf, 1999. [3] Craig S Petrie and J Alvin Connelly, “ A Noise-Based IC Random Number Generator for Applications in Cryptography” IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS—I: FUNDAMENTAL THEORY AND APPLICATIONS, VOL. 47, NO. 5, MAY 2000 [4] Barry paton, Dalhousie University,” Fundamentals of Digital Electronics” March 1998 Edition