[Cryptech Tech] Dieharder test of Cryptech RNG data

[Павел Шатов]

On 04.04.2015 10:56, Joachim Strömbergson wrote:
> Aloha!
>
> Basil Dolmatov wrote:
>> I need schematic, description and bunch of data for test.
>
> And by schematic you actually mean block/functional diagram I hope, not
> electrical schematics?
>

What's wrong with electrical schematics? I would like to have a look at 
it too. To be honest, I did not completely understand Fredrik's 
explanation of how avalanche entropy source works. In his letter he 
wrote, that -15V was used to power it, but in the attached schematics 
(http://wiki.cryptech.is/raw-attachment/wiki/AlphaBoardComponents/alpha_board_noise_source.pdf) 
+12V is shown instead.

There's no power supply regulator in the attached schematics. As far as 
I remember, Fredrik told us, that he evaluated three different linear 
regulators, but then decided to use two switching regulators in series. 
So, how is avalanche circuit powered now?

I also don't quite understand why charge pumps are used? As far as I 
know, they have very limited output current, while during avalanche 
breakdown large current flows through transistor. Is this okay?

What signal is fed into FPGA, btw? TP19 ("AMPLIFIED")? Is it okay to 
feed analog signal into digital input buffer?

I'm asking all these questions, because TRNG is a critical component of 
our system. I understand, that analog circuit design requires 
experimentation and tweaking, but once we have a stable working circuit, 
it should be captured and documented. This proven schematic should be 
given to BitSim guys along with instructions to just copy and paste it 
into Alpha board as is without any modification.

--
With best regards,
Pavel Shatov