[ANN] Sfards:SF100, the first 28nm Dual-Mode Miner is accepting pre-order now

[dogie]

Interesting data sheets, suggests dual mode may be viable compared to a single mode. Will be interesting what the final product will be 'stock-ed' at as GH / power has quite a large range tremendously. Don't have a complete data curve so these are just arbitrary points for now.

BTC only:
72GH @ 0.32W/GH
152GH @ 0.64W/GH.

[1713953870]

1713953870

[1713953870]

1713953870

[1713953870]

1713953870

[J4bberwock]

GC3328 

Anyway, interesting specs.

Reference design will help too.
Now working on a design while waiting for availability and pricing of the sample chips next week.

[philipma1957]

Interesting data sheets, suggests dual mode may be viable compared to a single mode. Will be interesting what the final product will be 'stock-ed' at as GH / power has quite a large range tremendously. Don't have a complete data curve so these are just arbitrary points for now.

BTC only:
72GH @ 0.32W/GH
152GH @ 0.64W/GH.

as a higher cost of power miner  the   0.32W/gh at the chip is worthless

If it is  at the wall I can mine with it.  I will study the chart over the next 10 minutes
 it looks like 0.6 volts is efficiency mode for btc

I do not know how stable the low power setting is but it is 11 watts a chip
I do not know how stable the high power setting is but it is 97 watts a chip

So a 20 chip box according to this could swing from as low as

220 watts

to as high as--------    720gh

1940 watts---------- 3040gh

All on a btc level.

this big swing really helps the small miner.

This difficulty adjustment renting to nice hash was as high as 0.0142  so crank to a high setting.
Other times getting 0.0102 from f2pool was best so lower to  800gh .

This type af gear is very good for me as a higher power cost miner.

here are both charts:

[Dexter770221]

Need for dual DC/DC converters increasing costs very sharply. Price for this chip must be in 20$ range to be competitive for example with bitmain. Efficiency doesn't look to promising. 0.32W at chip level means ~0.4W at wall. With good quality (gold or better) PSU.
Can't figure out what that FBB voltage is...

[TheRealSteve]

Can't figure out what that FBB voltage is...

forward body bias - see chip datasheet

[dogie]

Can't figure out what that FBB voltage is...

forward body bias - see chip datasheet

Body bias involves connecting the transistor bodies to a bias
network in the circuit layout rather than to power or ground.
The body bias can be supplied from an external (off-chip) source
or an internal (on-chip) source. In the on-chip approach, the
design usually includes a charge pump circuit to generate a
reverse body bias voltage and/or a voltage divider to generate
a forward body bias voltage. Reverse body bias, which involves
applying a negative body-to-source voltage to an n-channel
transistor, raises the threshold voltage and thereby makes the
transistor both slower and less leaky. Forward body bias, on the
other hand, lowers the threshold voltage by applying a positive
body-to-source voltage to an n-channel transistor and thereby
makes the transistor both faster and leakier. The polarities of the
applied bias described above are the opposite for a p-channel
transistor.

So it saves power by utilising a non 0V ground?

[Dexter770221]

Thanks, datasheet downloaded. So many voltages....

[alh]

My simplistic read of the Power/Freq/Voltage table suggests that they filled in values for some "reference" points. I am not sure we should interpret that to mean that ONLY .6V and .8V are allowed. The example of the SP20 suggests that it has a "variable" range DC to DC converter, within limits. The same goes for frequencies.

I am surprised also by the comment about the cost of such a DC2DC gadget. It seems like that, and an adjustable frequency gadget are pretty common these days, on a whole range of mining devices. Obviously there are variety of "non functional" combinations (e.g. Min volts and Max Frequency), as well as "poor efficiency" (e.g. Max Volts and Min Frequency). Beyond that it tends to be a limit of software on the extent folks are allowed to twist the Freq/Volt "knobs".

Not surprisingly, the Low Volts and Low Frequency setting yields the best efficiency.

This seems like pretty standard ASIC stuff doesn't it?

[dogie]

I am surprised also by the comment about the cost of such a DC2DC gadget. It seems like that, and an adjustable frequency gadget are pretty common these days, on a whole range of mining devices.

The commonality of components doesn't make them cheap. High amp DC-DC is expensive.

[philipma1957]

I am surprised also by the comment about the cost of such a DC2DC gadget. It seems like that, and an adjustable frequency gadget are pretty common these days, on a whole range of mining devices.

The commonality of components doesn't make them cheap. High amp DC-DC is expensive.

if you want hi amp low ripple and 92% or more efficiency they cost.

somewhere I read a 20 chip machine  if it can not clock under the .6 volts  the low setting will give  .4 watts at the wall like the sp20's do on super low clocks.

not impressed so far but maybe I am missing something or just a bit burnt out by  asic gear.

[bennybong]

Not that I am a fan of litecoin, but being able to mine both at the same time is a pretty cool feature. If all ASICs use this technology in the future then the litecoin network will become bigger and bigger... Maybe LTC isn't dead and useless after all?

[notlist3d]

Not that I am a fan of litecoin, but being able to mine both at the same time is a pretty cool feature. If all ASICs use this technology in the future then the litecoin network will become bigger and bigger... Maybe LTC isn't dead and useless after all?

I was a huge fan of scrypt at one time.  That was until the gear dropped over night on worth.  I almost lost some serious money.

Luckily I rented whole time I had machine so I did ROI..... but  was tightest margin I've ever had.   

I'm more interested in BTC specs personally.

[brontosaurus]

I am surprised also by the comment about the cost of such a DC2DC gadget. It seems like that, and an adjustable frequency gadget are pretty common these days, on a whole range of mining devices.

The commonality of components doesn't make them cheap. High amp DC-DC is expensive.

Only if you don't know how to design them properly.

[dogie]

I am surprised also by the comment about the cost of such a DC2DC gadget. It seems like that, and an adjustable frequency gadget are pretty common these days, on a whole range of mining devices.

The commonality of components doesn't make them cheap. High amp DC-DC is expensive.

Only if you don't know how to design them properly.

That's like saying cars cost less to buy if you're a good driver.

[brontosaurus]

I am surprised also by the comment about the cost of such a DC2DC gadget. It seems like that, and an adjustable frequency gadget are pretty common these days, on a whole range of mining devices.

The commonality of components doesn't make them cheap. High amp DC-DC is expensive.

Only if you don't know how to design them properly.

That's like saying cars cost less to buy if you're a good driver.

No, it's not. A poorly designed power supply can end up costing a lot more than a well designed one. The car analogy is nonsense. Most electronic engineers are not familiar with high current low voltage power supply design, its a specialist area and needs careful selection of components, not to   mention circuit board tracking that provides very low resistance paths (and connections). But the world is full of 'experts', is it not, and that's why shitty designs often result. People simply don't accept their limited knowledge of technical subjects and so don't read enough.

[pekatete]

I am surprised also by the comment about the cost of such a DC2DC gadget. It seems like that, and an adjustable frequency gadget are pretty common these days, on a whole range of mining devices.

The commonality of components doesn't make them cheap. High amp DC-DC is expensive.

Only if you don't know how to design them properly.

That's like saying cars cost less to buy if you're a good driver.

Keep your drivel to the bitmain threads!
DC to DC components do have a cost, but the design as a whole can be more efficient (power efficiency and ROI wise) than without.

[brontosaurus]

I am surprised also by the comment about the cost of such a DC2DC gadget. It seems like that, and an adjustable frequency gadget are pretty common these days, on a whole range of mining devices.

The commonality of components doesn't make them cheap. High amp DC-DC is expensive.

Only if you don't know how to design them properly.

That's like saying cars cost less to buy if you're a good driver.

Keep your drivel to the bitmain threads!
DC to DC components do have a cost, but the design as a whole can be more efficient (power efficiency and ROI wise) than without.

Let the man speak. It's good to have discussions so that the community at large can get a variety of opinions, then make up their own mind as to what's information and what's drivel. Maybe that way some of the drivel might disappear.

And you're absolutely right about the overall efficiency of a product, very good insight.

See? You've probably to taught a good few readers to think differently about design.

[Bicknellski]

I am surprised also by the comment about the cost of such a DC2DC gadget. It seems like that, and an adjustable frequency gadget are pretty common these days, on a whole range of mining devices.

Only if you don't know how to design them properly.

Keep your drivel to the bitmain threads!
DC to DC components do have a cost, but the design as a whole can be more efficient (power efficiency and ROI wise) than without.

Let the man speak. It's good to have discussions so that the community at large can get a variety of opinions, then make up their own mind as to what's information and what's drivel. Maybe that way some of the drivel might disappear.

And you're absolutely right about the overall efficiency of a product, very good insight.

See? You've probably to taught a good few readers to think differently about design.

If you ignore Adam then you can just cut to reading what people that are not bent on shilling for another company have to think. Big difference between being openly hostile and slagging the competition and having a vigorous debate about the potential of this chip.

Thanks to those that cut through his bullshit. Just stop quoting him so I don't have to read it.

[Dexter770221]

.....
Really neat, but we still don't know if this is at the wall yet?

It's a chip datasheet. "At wall" depends on many factors. DC/DC converter and PSU efficiency. So, if thats not specified all data covers only chip.

[dogie]

The commonality of components doesn't make them cheap. High amp DC-DC is expensive.

Only if you don't know how to design them properly.

That's like saying cars cost less to buy if you're a good driver.

No, it's not. A poorly designed power supply can end up costing a lot more than a well designed one. The car analogy is nonsense.

You're arguing that off the shelf components cost more 'if you design them wrong', which doesn't make sense. If however you were trying to say that 'if you design the system wrong, and use more components than you should...', then sure but that's not what we were discussing.

We already know if that if you use 10 gold ingots to wedge open a door, its going to cost more than if you were to use 5 gold ingots to do the same job, its just a given. What we were actually discussing was the merits of using gold ingots to wedge open a door in the first place.

DC to DC components do have a cost, but the design as a whole can be more efficient (power efficiency and ROI wise) than without.

No one said anything about comparing high amp DC-DC to no DC-DC. But now we are, are you actually trying to argue that string design on small chips makes them less efficient and more expensive?

Big difference between being openly hostile and slagging the competition and having a vigorous debate about the potential of this chip.

Says the guy who entirely just ignored the entire debate to attack me?