[Cryptech Tech] Dieharder test of Cryptech RNG data

[Павел Шатов]

On 04.04.2015 19:40, Fredrik Thulin wrote:
> On Saturday, April 04, 2015 01:18:46 PM Павел Шатов wrote:
>> 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_boar
>> d_noise_source.pdf) +12V is shown instead.
>
> I'm glad you asked so we can sort out the confusion.
>
> The -15V refers to this hardware (software alongside in the repository)
>
> http://wiki.cryptech.is/browser/user/ft/stm32-avalanche-noise/hardware/rev09/rev09-sch.pdf
>
> The Novena entropy noise source board which I believe is you have is almost
> identical to this, and I've attached the schematics.
>
>> 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?
>
> There is a current limiting resistor, which probably also plays an important
> role in preventing fast aging of the noisy diode/transistor.
>
> I don't remember the exact value, but I think the current consumption was 47
> mA for the avalanche circuitry at -15V.
>
>> What signal is fed into FPGA, btw? TP19 ("AMPLIFIED")? Is it okay to
>> feed analog signal into digital input buffer?
>
> Right, I have a Schmitt trigger on the AMPLIFIED signal to digitize the signal
> in the current Novena board. That might be appropriate to add for the Alpha
> board too. You are a good proof-reader - thanks.
>

Thank you, Fredrik! rev02_sch.pdf is exactly what I was asking for. Can 
I have a look at rev02.sch too, please? As far as I understand it was 
designed using EAGLE software?

--
With best regards,
Pavel Shatov