Re: gEDA-user: Design with a 144 pin QFP

2008-02-03 Thread ST de Feber
Hello All, Thanks for the advice. I'll give it a go. The device in mind is an Altera Cyclone-3 FPGA. Most probably the ep3c5. As for the function, it will do audio-dsp like functions. I2S in, 3 to 4 channel FIR filtering (1024-tap) and I2S out. When not filled completely i will try to add a

Re: gEDA-user: Design with a 144 pin QFP

2008-02-03 Thread Larry Doolittle
Simon - On Sun, Feb 03, 2008 at 01:26:40PM +, ST de Feber wrote: The device in mind is an Altera Cyclone-3 FPGA. Most probably the ep3c5. FPGAs are the easiest chips to lay out, as long as you keep an open mind about pin assignments until you're halfway through the layout. Unless there is

Re: gEDA-user: Design with a 144 pin QFP

2008-02-03 Thread Ben Jackson
On Sun, Feb 03, 2008 at 01:26:40PM +, ST de Feber wrote: The device in mind is an Altera Cyclone-3 FPGA. Most probably the ep3c5. My board has an EP2C8. Assuming you have a single IO voltage plus the core you can do this in 4 layers. I had GND and 3.3V on the planes. The 1.2V is made

Re: gEDA-user: Design with a 144 pin QFP

2008-02-03 Thread Daniel O'Connor
On Mon, 4 Feb 2008, Larry Doolittle wrote: On Sun, Feb 03, 2008 at 01:26:40PM +, ST de Feber wrote: The device in mind is an Altera Cyclone-3 FPGA. Most probably the ep3c5. FPGAs are the easiest chips to lay out, as long as you keep an open mind about pin assignments until you're

gEDA-user: Design with a 144 pin QFP

2008-02-02 Thread ST de Feber
Dear all, Has any one of you designed a PCB with a 144 pin QFP/TQFP package ? (with or without exposed die pad) If so, is one of you so kind to show me the PCB files ? How many layers will such a board have ? Until recently i designed boards with a max of 44 (ic) pins. So i do not feel

Re: gEDA-user: Design with a 144 pin QFP

2008-02-02 Thread Steve Meier
Simon, Get your confidence up 144 pin qfp is very standard. Layers. Maybe 3 for power and ground (Vcci, Vccio and ground) 3 for signals Top, bottom and one in the middle. Even if you need analog then you can either add a few more layers or carefully manage the layers that you have. i.e if

Re: gEDA-user: Design with a 144 pin QFP

2008-02-02 Thread Dave McGuire
On Feb 2, 2008, at 7:09 AM, ST de Feber wrote: Has any one of you designed a PCB with a 144 pin QFP/TQFP package ? (with or without exposed die pad) If so, is one of you so kind to show me the PCB files ? How many layers will such a board have ? Until recently i designed boards with a max

Re: gEDA-user: Design with a 144 pin QFP

2008-02-02 Thread Ben Jackson
On Sat, Feb 02, 2008 at 12:09:37PM +, ST de Feber wrote: Has any one of you designed a PCB with a 144 pin QFP/TQFP package ? (with or without exposed die pad) I just made a board with a QFP208 (0.5mm), 100 (0.65mm rectangular) and 80 (0.65mm square). How many layers will such a board