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Max v cpld dpll

Altera_Forum
Honored Contributor II
2,329 Views

Hi All, 

I am new to the Altera CPLDs. Come from the X-Company side of things. The Max V CPLD looks really cool. What with user Flash memory, Internal programmable Oscillator, low power states. Is there a DPLL available on these devices. I found references to that on the product landing page but the data sheet does not talk about that. Can someone please clarify? 

 

thanks 

ANanth
0 Kudos
13 Replies
Altera_Forum
Honored Contributor II
437 Views

MAX V effectively is MAX II, with identical specification and core structure, and minimal changes, extending Z (zero power) to higher densities and introducing new packages. Rated number of programming cycles has been gracefully increased from 100 to 1000 for the UFM. 

 

MAX II/V has an internal RC oscillator, required for operation of the internal flash and also exposed to user logic. It's not programmable. No new clock processing features are provided according to the datasheet. 

 

The DPLL point is interesting indeed. It still written on the MAX V product page. 

http://www.altera.com/products/devices/cpld/max-v/mxv-index.jsp 

 

 

--- Quote Start ---  

...features including: 

Digital PLLs (DPLLs), which enable flexible implementation of designs requiring frequency multiplication or phase shifting 

--- Quote End ---  

 

 

It's also written in the MAX V solution sheet http://www.altera.com/literature/po/ss-maxv-cplds.pdf 

 

--- Quote Start ---  

MAX V Silicon Features and Benefits 

... 

Phase-locked loops (PLLs) - Digital PLL implementation provides flexible implementation for designs needing frequency multiplication or phase shifting. 

--- Quote End ---  

 

 

So either the "clock network" chapter has been forgotten in the MAX V datasheet, or the feature has been previously planned but wasn't implemented, or it has been implemented, but doesn't work.
Grantwt
Beginner
300 Views

Is there anywhere I find information on the number of PLL available the operating frequency range and the loop filter time constant. There seem to be a lot information about the MAX V chips, next nothing on the DPLL's  and the possible configurations. Are there any pdf files I can look at with this information in?

 

 

Altera_Forum
Honored Contributor II
437 Views

The DPLL feature on MAX V devices is interesting. However, the overview page has this note: 

 

 

--- Quote Start ---  

 

Note: 

1. Digital PLL is an optional intellectual property (IP) that can be instantiated into unused LEs. 

--- Quote End ---  

 

 

So is it just an IP feature? No specific silicon support? If that is the case, then why it is specific and restricted to MAX V?
Altera_Forum
Honored Contributor II
437 Views

Hi All, 

Thanks for chiming in. How does the "instantiating optional IP" generally work with the A devices? Is it one within Quartus, like Megacore function maybe??  

 

With X devices it is done by Coregen. But Coregen is restricted to FPGAs only not for the Coolrunner-II CPLDs.  

 

thanks 

Ananth
Altera_Forum
Honored Contributor II
437 Views

 

--- Quote Start ---  

the overview page has this note 

--- Quote End ---  

 

Where did you read this? 

 

Generally, MAX II as well as MAX V are small SRAM based FPGAs rather classical CPLDs, the device core is almost identical to Cyclone III, but it lacks internal RAM, hardware PLLs and some interface types. In so far, the prerequisites to create a PLL in LEs would be the same for Cyclone or MAX II/V devices. In the above quoted document a functionality similar to the dedicated hardware PLLs of Cyclone and Stratix FPGA is described (e.g. allowing frequency multiplication and phase shifting). It can't be done will discrete time PLLs, that are suitable for low output frequencies at a fraction of the input clock only. 

 

There's a principle method to implement a PLL in ASIC gates respectively FPGA logic cells by utilizing programmable delay line oscillators. German company Chip Cologne has filed a patent for it and is selling it as an ASIC IP. 

http://www.colognechip.com/asic/ip-cores/digicc-pll-techn.pdf 

But it seems unlikely, that this technique has been intended for the said MAX V PLLs. 

 

As expectable, Altera Quartus V10.1 does not provide a DPLL Megafunction for MAX V.
Altera_Forum
Honored Contributor II
437 Views

 

--- Quote Start ---  

Where did you read this? 

--- Quote End ---  

 

 

As I said, it is in the Max V overview page: 

 

http://www.altera.com/products/devices/cpld/max-v/overview/mxv-overview.html 

 

 

--- Quote Start ---  

In the above quoted document a functionality similar to the dedicated hardware PLLs of Cyclone and Stratix FPGA is described (e.g. allowing frequency multiplication and phase shifting). It can't be done will discrete time PLLs, that are suitable for low output frequencies at a fraction of the input clock only. 

--- Quote End ---  

 

 

I agree. But the fact is that Altera is claiming it is an IP, and Altera documentation doesn't mention, so far, any silicon support. So something seems wrong, but we don't really know exactly what.
Altera_Forum
Honored Contributor II
437 Views

Thank you, for some reason, I didn't look back to the left side of the devices page. 

 

 

--- Quote Start ---  

Altera documentation doesn't mention, so far, any silicon support 

--- Quote End ---  

 

Furthermore, the MAX V chip layout shown in the device manual is identical to MAX II. So there's effectively no room for it. 

 

--- Quote Start ---  

So something seems wrong, but we don't really know exactly what. 

--- Quote End ---  

 

Yes. Of course a MAX V PLL would be an interesting feature. So let's wait for a clarification.
Altera_Forum
Honored Contributor II
437 Views

The MAX V device handbook is presently updated, but V1.1 still misses a clarification about the anounced "Digital PLL" feature. The term is listed as a pdf keyword for the document, but can't be found anywhere. 

 

I also noticed, that the MAX V CPLD Architecture page locates a Digital PLL in the oscillator block, which sounds reasonable. 

http://www.altera.com/products/devices/cpld/max-v/overview/architecture/mxv-architecture.html 

 

I filed a service request asking for a clarification.
Altera_Forum
Honored Contributor II
437 Views

I have also noticed the same info. 

The problem is i need a quickly ask to this question. 

Does someone that has already used MAXV tell us if there is (or not) that misterious DPLL. 

 

Furthermore i think to be urgent an explanation on this point by the ALTERA support.  

 

Thanks to all.
Altera_Forum
Honored Contributor II
437 Views

The problem has been that urgent for me, because I'm not planning to use MAX V for a concrete product now, thus I didn't ask before. Getting no answer yet after three days, suggests that my question couldn't answered by the support stuff on their own. 

 

--- Quote Start ---  

So my simple question is: What's are the presently available and planned clock processing features of MAX V? Will a digital PLL be available and what's the specification? 

--- Quote End ---  

 

Actually, this isn't surprizing at all, otherwise Altera marketing had put an end to the curious show before.  

 

Perhaps you should ask your local FAE or distributors technical staff in the same regard.
Altera_Forum
Honored Contributor II
437 Views

Does anyone already use the MAX5 CPLD ?

Altera_Forum
Honored Contributor II
437 Views

Typically, I don't line up as a first implementer. But if I had the device under my fingertips, I most likely won't be aware of hidden or unsupported features. Apart from the zero power feature, everything in the device handbook looks similar to MAX II. 

 

Actually having the DPLL option would open new applications for the device, so I'm seriously interested now. A recent update to my support request (from sunday) promises an early reply. I'll keep you informed. If anyone else got substantial news from Altera in the meantime, I would be glad to hear about. 

 

Regards, 

Frank
Altera_Forum
Honored Contributor II
437 Views

Support says: 

 

--- Quote Start ---  

Regarding your MAX V Digital PLL request, unfortunately our marketing and engineering teams still is in progress characterizing and finalizing the details. We do not have much information to share out at this moment. The tentative target for this feature to be supported by Quartus II software will be by end of this year. 

--- Quote End ---  

 

Apparently, the MAX V product pages are missing a preview title line.
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