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嗨,
我目前正在设计一个具有两种电源模式的系统: 低功耗模式,仅运行FPGA和总线接口,均为3.3V(VCCAUX,VCCIO) 一个正常的操作模式,我拥有通常存在于嵌入式环境中的所有东西(DDR2 Ram,Prom,高速接口等) 我想做的是将DDR2接口的VCCO连接到DDR2电源,但这意味着当我打开设备电源时,它最初为0V,并且可能随时关闭。 这对于连接到该端口的所有设备都是可以的,但是FPGA会介意吗? 据我所知,推荐的电源序列是VCCINT - > VCCAUX - > VCCIO。 如果VCCIO在0V内保持很长时间,那会有问题吗? 如果仅使用其他存储体,FPGA配置是否会完成并且FPGA是否会开始运行? 谢谢, Bonf。 以上来自于谷歌翻译 以下为原文 Hi, I am currently designing a System with two power modes: A low power mode, where only the FPGA and a Bus Interface is running, both at 3.3V (VCCAUX, VCCIO) A normal operating mode, where I have all the stuff usually present in an embedded environment (DDR2 Ram, Prom, High Speed Interfaces etc.) What I would like to do is to attach the VCCO of the DDR2 Interface to the DDR2 supply, but this would mean that when I power up the device it is initially at 0V, and may be switched off any time. That would be ok for all the devices attached to that port, but would the FPGA mind? As I understand the recommended power sequence is VCCINT -> VCCAUX -> VCCIO. If VCCIO would stay at 0V for many seconds, would that be a problem? Would the FPGA configuration complete and would the FPGA start running, if only the other banks are used? Thanks, Bonf. |
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bonf,除非数据手册禁止,否则您可以根据需要关闭任何电源。监控电源ON的三个电源是配置组的Vccint,Vccaux和Vcco。
如果这三个中的任何一个低于跳变点(电源电压的~1 / 2),那么器件将断电或失去配置,并且必须重新配置(将尝试)这些电源全部恢复时。那些,那些 上电和配置需要三个电源。 您的设计可能还希望其他IO银行打开电源(我无法预测您的设计将做什么:您必须对其进行测试以确保它能够满足您的需求)。 Austin Lesea主要工程师Xilinx San Jose 以上来自于谷歌翻译 以下为原文 bonf, Unless prohibited by the data sheet, you may power down any supply, for as long as you like. The three supplies monitored for power ON are Vccint, Vccaux, and Vcco for the config bank. If any one of those three goes below the trip point (~1/2 the supply voltage), then the device will power down, or lose configuration, and must reconfigure (will try to) when those supplies are all restored. So, those three supplies are required to power ON, and configure. Your design might also want to have other IO banks powered ON (I can't predict what your dedsign will do: you have to test it to be sure it does what you want). Austin Lesea Principal Engineer Xilinx San Jose |
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哇,谢谢这是一个非常快速的回复,真的很有帮助。
但现在我遇到了另一个相关的问题: 我将使用LX150,并且希望在启动时不使用电源而保留Bank 0。 HSWAPEN将如何反应? 1)它很低,所以Pull-Ups被停用 2)它等于VCCO,因此启动了上拉 3)它没有证件,所以上帝知道。 即使可以测量,它也可能会随着硅片,ise,编程电缆或加州天气的任何新修订而改变。 更一般地说:如果我读取未通电的端口的输入,我会读取1或0(或未定义的x)吗? 谢谢,邦弗。 以上来自于谷歌翻译 以下为原文 Wow, thanks that was a really fast reply, and really helpful. But now I have run into another related problem: I will be using the LX150, and would like to leave Bank 0 without power on startup. How will HSWAPEN react? 1) It's low, so Pull-Ups are deactivated 2) It's equal to VCCO, so pull-ups are activated 3) It's undocumented, so god knows. Even if it can be measured it might change with any new revision of the silicon, the ise, the programming cable or the weather in california. And more generally: If I read an input of a port that is not powered, will I read a 1 or 0 (or a undetemined x)? Thanks, Bonf. |
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bonf,如果银行不是配置银行,则设备开机并进行配置。
如果HSWAPEN很高,你在配置时得到上拉,如果低,你得到三态。 Sine Vcco不在那家银行,你什么也得不到。 所有这些都是来自每个IO引脚的背面的Vcco引脚的固有(内置)二极管,因此如果有任何驱动电压到存储体上的任何这些引脚,那么将通过二极管到存储体的Vcco( “IO电源开启”需要不到2 mA的电流。如果你试图读取一个没电的银行,我不知道你得到了什么。 我会假设一个或零,但也许它是随机的。 我不知道。 Austin Lesea主要工程师Xilinx San Jose 以上来自于谷歌翻译 以下为原文 bonf, If the bank is not the config bank, the the device powers on, and configures. If the HSWAPEN is high, you get pullups while you configure, if low, you get tristate. Sine Vcco isn't on that bank, you get nothing. All that is there is the intrinsic (built in) diode to Vcco pin of the back from every IO pin, so if anything drives a voltage to any of these pins on the bank, that will go through the diode to Vcco of the bank (it takes less than 2 mA to 'power on' an IO bank). If you try to read an un-powered bank, I have no idea what you get. I would assume either one or zero, but maybe it is random. I do not know. Austin Lesea Principal Engineer Xilinx San Jose |
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略微纠正:
如果HSWAPEN很高,你在配置时得到上拉,如果低,你得到三态。 实际上,情况正好相反。 HSWAPEN = 0可以获得弱上拉,HSWAPEN = 1可以获得三态(无上拉)。 见UG380表2-6。 - 鲍勃埃尔金德 签名:新手的自述文件在这里:http://forums.xilinx.com/t5/New-Users-Forum/README-first-Help-for-new-users/td-p/219369总结:1。 阅读手册或用户指南。 你读过手册了吗? 你能找到手册吗?2。 搜索论坛(并搜索网页)以寻找类似的主题。 不要在多个论坛上发布相同的问题。 不要在别人的主题上发布新主题或问题,开始新的主题!5。 学生:复制代码与学习设计不同.6“它不起作用”不是一个可以回答的问题。 提供有用的详细信息(请与网页,数据表链接).7。 您的代码中的评论不需要支付额外费用。 我没有支付论坛帖子的费用。 如果我写一篇好文章,那么我一无所获。 以上来自于谷歌翻译 以下为原文 slight correction: If the HSWAPEN is high, you get pullups while you configure, if low, you get tristate. Actually, it's the opposite. HSWAPEN=0 gets you weak pullups, HSWAPEN=1 gets you tri-state (no pullups). See UG380 Table 2-6. -- Bob Elkind SIGNATURE: README for newbies is here: http://forums.xilinx.com/t5/New-Users-Forum/README-first-Help-for-new-users/td-p/219369 Summary: 1. Read the manual or user guide. Have you read the manual? Can you find the manual? 2. Search the forums (and search the web) for similar topics. 3. Do not post the same question on multiple forums. 4. Do not post a new topic or question on someone else's thread, start a new thread! 5. Students: Copying code is not the same as learning to design. 6 "It does not work" is not a question which can be answered. Provide useful details (with webpage, datasheet links, please). 7. You are not charged extra fees for comments in your code. 8. I am not paid for forum posts. If I write a good post, then I have been good for nothing. |
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奥斯汀,
谢谢回复。 我问的是与这样的设置有关: Bank 0 - VCCO = 0V(HSWAPEN在此银行) Bank 1 - VCCO = 1.8V一些I / O接口 Bank 2 - VCCO = 3.3V配置在此Bank上 Bank 3-5 - VCCO = 0V(在低功耗模式下禁用) 现在当Init变高时,HSWAPEN无动力。 当Bank 2完全供电时,配置将启动。 现在你说银行0和3-5将没有任何东西,因为没有权力。 问题是第1银行和第2银行是否会出现上拉? 我现在决定不这样做,因为风险太大,但我只是想知道...... 这在电源排序方面也很有意思,因为如果答案是不清楚将会发生什么,那么具有HSWAPEN的Bank必须在配置之前被供电,否则配置期间的状态是不确定的。 Bonf。 以上来自于谷歌翻译 以下为原文 Austin, thanks for the reply. What I was asking was related to a setup like this: Bank 0 - VCCO = 0V (HSWAPEN is on THIS Bank) Bank 1 - VCCO = 1.8V Some I/O Interface Bank 2 - VCCO = 3.3V Configuration is on this Bank Bank 3-5 - VCCO = 0V (disabled in low power mode) Now when Init goes high HSWAPEN is unpowered. Configuration will kick in, as Bank 2 is fully powered. Now as you said Bank 0 and 3-5 will not have anything, as there is no power. The question is will Bank 1 and Bank 2 have pullups or not? I have decided by now not to do this, as it is too risky, but I'd just like to know... This is also interesting when it comes to power sequencing, because if the answer is that it is not clear what will happen it follows that the Bank with HSWAPEN has to be powered BEFORE configuration, else the state during configuration is undetermined. Bonf. |
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鲍勃,
这是我的错误,与奥斯汀无关。 谢谢你指出来。 Bonf。 以上来自于谷歌翻译 以下为原文 Bob, that was my error, nothing to do with Austin. Thanks for pointing it out. Bonf. |
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有趣的是,在UG380中,所有的原理图都显示Vcco0连接到电源。
这似乎意味着必须进行配置。 我可以想象多种方式 接地可能会影响HSWAPEN引脚。 一个是因为它会看起来很低 上拉到Vcco0(现在在地面)。 另一个可能是没有Vcco0,输入缓冲区会 没有供电,并不清楚这对内部电路意味着什么。 在另一 任何人都有一个单独连接这个银行电源的电路板可以检查状态 由系统检测到,因为它显示在状态寄存器中,使用Impact可读。 - Gabor - Gabor 以上来自于谷歌翻译 以下为原文 It's interesting that in UG380, all of the schematic diagrams show Vcco0 hooked up to a supply. This seems to imply that it is necessary for configuration. I could imagine multiple ways that grounding it could affect the HSWAPEN pin. One would be that it would look low due to the pullup to Vcco0 (now at ground). Another might be that without Vcco0, the input buffer would not be powered, and it's not clear what that would mean to the internal circuitry. On the other hand, anyone with a board that has this bank power wired separately could check the state sensed by the system because it shows up in the status register, readable using Impact. -- Gabor -- Gabor |
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好的,好吧,因为HSWAPEN在一个没有Vcco的银行......它将是上拉或三态,它可能是随机的。
如果这是一个问题,那么启动它。 所有IO三态的存储区大约为2 mA,那么节省多少电量? Austin Lesea主要工程师Xilinx San Jose 以上来自于谷歌翻译 以下为原文 All, OK, so since HSWAPEN is in a bank with no Vcco... It will be either pullup, or tristate, and it may be random. If that is a problem, then power it up. A bank with all IO tristate is ~ 2 mA, so how much power are you saving? Austin Lesea Principal Engineer Xilinx San Jose |
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