Hi If you are using the Printable PDF option in the dashboard properties, I do not think you can download the file without prompt values.
You can down load the analysis using the Export Option in your Edit Dashboard -> Report Properties -> Report Links
Here you can enable the option to download a specific analysis without any dashboard prompts but if you have multiple reports in your dashboard, as far as my knowledge goes there is no way to disable the prompts
Please mark if it helps;....
This can be done, even with multiple analyses, but to my knowledge you need to make use of BI Publisher (fortunately, it's integrated with OBIEE so very very simple to set up). Let's imagine you have three analyses that you would like to create a single PDF export for. You can create a "Data Model" that has three data sets (yeah, you guessed it, one Data Set per each OBIEE analysis). Then you can create an RTF template which will make use of each of these three data sets and compile the results of them in to one report. This report can then be embedded in the dashboard very easily (drag and drop as you would an analysis) and of course you can export a PDF from it.
You also have the advantage of having much more control over how you want the results from the analyses to appear on the report.
This will get you up and running if you don't have BI Publisher experience : Getting Started with Oracle BI Publisher 188.8.131.52.0 and higher
Let me know if you have any specific problems getting it how you want.