Z77X-UP7 Preview - VRM Analysis

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VRM Analysis:

Z77X-UP7 Preview

 

 "We have to remove the heatsinks to see the real motherboard" -Steven B. (2010)

Z77X-UP7 Preview

 Look at how many phases can exist and still leave room for other things!

 

Z77X-UP7 Preview

 Here we have the 32 phase VRM which is made up of 32x IR3550 and some of the most shiny mirror finished inductors I have ever seen.

 

Z77X-UP7 Preview

 I made a diagram to show you exactly how the VRM is constructed. The IR3563A is an 8 phase PWM, it provides 8 PWM outputs which are then quadroupled by 8x IR3599 which are quadrouplers. They take 1 PWM input and make it 4 PWM outputs. Now the way this quadrupler works is pretty fancy, it can do 3 modes. First it can be disabled if the PWM turns off one of its phases then the quadrupler will shut down and so will 4 phases. Then it can operate normally in which every time the PWM fires at one of its channels(phases) then the quadroupler fires only 1 of its phases, the next cycle it will fire the second phase on the quadroupler, then the 3rd cycles it will fire the 3rd phase. In theory every full cycle only 8 IR3550 will be turned on, one from each IR3599, that would make this 32 phase VRM really a total of four full 8 phase VRMs. That is why the VRM can run very cool as you only heat up phases as needed. However there is one other mode of operation and that is when the IR3599 is told to turn on all of its phases, while doing that the PWM could also harness the power of all its phases and align all the channels and thus turn on all 32 IR3550 for a huge 32 phase VRM, that is how GIGABYTE was able to pull 2000W of power. IR had told me at Computex that the UP7 would be able to have a giant 32 phase waveform, thus it is pretty big VRM and many would say overkill, however it also runs pretty cool for the amount of switching components available. In theory this is a good design for watercoolers who wont have any active cooling on the VRM, as this VRM can run without heatsinks as well and not get into any trouble. Now the quadroupler also cuts the max switching frequency in 1/4 of the original, however this isn't an issue as the IR3563A is capable of 2MHz according to IR, plus you don't' ever want to run the phases at anything over 300KHz anyways, which is what 1.2MHz effective at the PWM would produce.

 

Z77X-UP7 Preview

 IR3563A is a true 8+0 phase VRD12/12.5 certified DIGITAL PWM, a REAL DIGITAL PWM. This is IR's Latest and greatest, and has only been used on two other GIGABYTE boards before this one, each of those times in 8phase VRMs. The fact that everything in this VRM is made by IR except the PCB, the chokes, and the capacitors means that they all will work seamlessly and efficiently together. The best IR has to offer has been put on this motherboard.

 

Z77X-UP7 Preview

 Can you see me???

 

Z77X-UP7 Preview

 The chokes here are each capable of 30A, and they are a very nice ferrite SMD choke. SMD chokes are used here b/c of their size. The normal 60A Ultra Durable 5 chokes couldn't be used b/c of their size, however 30A is more than enough considering boards in this category from other top brands only can do about 35A. However here we have a ton more phases than any other z77 board.

 

Z77X-UP7 Preview

 A lot of backside IR3550.

 

Z77X-UP7 Preview

 IR3599 and IR3550 in an up-close shot.

 

Z77X-UP7 Preview

 An IR3570 is a 3+2 phase Digital PWM, here all 3 phases are used for the memory VRM, where GIGABYTE chose to use three IR3550, that is A LOT of power for the DIMMs.

The other +2 is routed for the iGPU.

 

Z77X-UP7 Preview

 Another IR3570 is routed to the VTT(VCCIO) and IMC(VCCSA) for independent control over each of those rails. They also use the IR3550.

 

Z77X-UP7 Preview

 Here is the last VRM I am going to show, it is used for the PEX8747 PCI-E switch chip, a single phase Richtek PWM and Rensas FETs.

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