对冷流道II和RAMP上电压进行电源排序需要多少延迟？

对于CoolRunner-II：
不需要Vccint / Vccio上升时间，也不需要Vccint / Vccio上电排序。
请访问http://www.xilinx.com/support/documentation/application_notes/xapp389.pdf
问候，
结



以下为原文

For CoolRunner-II:
There is no requirement for Vccint/Vccio rise time, nor is there a requirement for Vccint/Vccio power-up sequencing.
 
See http://www.xilinx.com/support/documentation/application_notes/xapp389.pdf
 
Regards,
Eze

嗨，Eze，
谢谢回复。
但这就是我所提到的文件，它清楚地说：
为CoolRunner-II CPLD供电
XAPP389（v1.1）2007年10月29日
www.xilinx.com
五
[R
2. V
CCINT
上升时间
负载电源应为V提供0V至1.8V电压
CCINT
尽快。
作为一般
准则，一个可以提供小于4毫秒的1.8V斜率的电源
推荐的。
为了达到这个4毫秒（或更快）的斜率，使用提供的“启用”功能
电源/稳压器。
通常情况下，缓慢的斜坡是由调节器引起的
始终启用。
因此，输出电压斜坡时间只能与输入电压一样快地斜坡上升
斜坡时间。
只有在输入电压达到时才能启用电源
最后一级。
3. V
CCINT
/ V
CCIO
上电顺序
对于其中V的设计
CCIO
和V.
CCINT
未连接到相同的电源（例如
V
CCINT
/ V
CCIO
驻留在不同的电压），建议有V
CCINT
斜坡前
V
CCIO
。
在I / O之前为内核供电是大多数Xilinx器件的良好实践。



以下为原文

Hi Eze,
Thanks for the reply. But thats the document I was refering to, it clearly says:
 
 
Powering CoolRunner-II CPLDsXAPP389 (v1.1) October 29, 2007www.xilinx.com5R2. VCCINTrise timeA loaded power supply should deliver 0V to 1.8V to VCCINTas quickly as possible. As a generalguideline, a power supply which can provide a 1.8V ramp rate of less than 4 ms isrecommended.In order to achieve this 4 ms (or faster) ramp rate, utilize the "enable" features provided bypower supplies/regulators. It is often the case that a slow ramp is caused by a regulator beingalways enabled. Thus, the output voltage ramp time can only ramp as fast as the input voltageramp time. The power supply should only be enabled when the input voltage has reached itsfinal level.3. VCCINT/VCCIOpower-up sequenceFor designs in which VCCIOand VCCINTare not connected to the same power supply (e.g.VCCINT/VCCIOreside at different voltages), it is recommended to have VCCINTramp beforeVCCIO. Powering up the core before the I/O is a good practice for most Xilinx devices.

上电顺序：Vccint和Vccio之间的任何延迟都可以使用
上升时间：越快越好



以下为原文

Power-up sequencing: any delay between Vccint and Vccio will work
 
Rise Time: the faster the better