FPGA or CPLD? Application question

[Sink0]

Hi, i need to create a M-LVDS nwtwork running at 50-100Mbps. As i could not
find any driver that could be placed to run that multdrop network (any
protocol and datalink designed with small and size variable packet (Max 256
bytes) would be suitable) i designed one myself on a FPGA. On the on the
uC/DSP side there is a 8/16 bits parallel interface and at the M-LVDS the
clock is recovered with oversampling the data (using the rise and fall edge
and a second clock with 90 degree phase as described in this paper:
**broken link removed**
.

The fisrt questions is: Is possible to implement such oversampling on a
CPLD? Does CPLDs got any kind of PLL or something like that?

Second: Do you think CPLDs are going to stay on the market for a long time?
Or they are going to disapear and there will be just FPGAs?

Third: This device must got a real small footprint. The best i found was a
EP1C3 of Altera, but any one knows how long is going to take until this
device is discontinued?

Any sugestion of using a CPLD or FPGA for this design, or sugestions of any
small fottprint (no BGA) FPGA of Altera or Xilinx (i got the download cable
of both and dont want to get a new one).

Thank you!

 

[farhada]

Answer to the first question is 'no' it maybe possible if you have a really large CPLD but I don't think those are way too expensive and too big for what you are looking for.

Second: Yes, CPLDs have a unique place on the market and many of them are used in industrial designs like automation, traction and aviation so they will be around at least 15-20 years more.

Third: take a look at devices from SiliconBlue their iCE65L01 comes in CS36 package, which is a 36-pin, 2.5 x 2.5 mm wafer-level chip scale package.

There are other alternatives such as these from Actel : Actel IGLOO nano Low Power FPGA

But the real small packages are always BGA, the smallest non-BGA is VQ100 that both Altera and Xilinx and others have.

Hope this is useful,
Best regards,
/Farhad Abdolian

 

[Sink0]

Prototype with BGA is way far expensive. Thats the problem. Its a price i dont want to afford hehe. But Thank you i guess i will have to stay with 100 pins.

But any ideal how long untill cyclone I or Spartan 3 familys are going to get discontinued? The problem is that all other do not offer a VQ100 package. Just bigger or BGA.

Completely offtopic. What kind of aplication a CPLD is used that makes it so unique?

 

[farhada]

I am doing BGA work at home and it is pretty straight forward. After a couple of misses, now I can solder BGAs (not really big ones but smaller ones) without any troubles.

I have no idea how long these ICs will be on the market. Both Altera and Xilinx have the tendency to drop their FPGAs without prior notice and then it will be up to you to find them on the market. You should ask your FAE for info.

CPLDs are unique because of their low power, small size, in-circuit-pgramability and price. In many applications they replace glue logic and replacing multiple standard 74xx type components. Also, they make it easy to support life long update of designs like what Xilinx and Altera do with their JTAG programmers.

 

[elec4fun]

Hello,

From my point of view CPLD have two avantages over FPGA:

- No need for external eeprom to store the configuration
- No need for multiple supply voltage

However, you don't have avantages of fpga....Choise depends on the situation.

 

[Sink0]

Hmm.. got the idea. But how do you handsold BGA chips? Any good advice? Guide? Video?


hehe

Thank you

 

[farhada]

Sure,
Take a look at these videos:

**broken link removed**

YouTube - BGA Soldering - Memory Swapping by Hand
YouTube - BGA rework by hand

 

[craftor]

From my point of view , CPLD is better for combinational logic circuit while FPGA is better for sequential logic circuit.