Is There A Such Thing As A Cheap Fpga?

...i.e. no need for a eval board...just a programmable chip that you can breadboard? I was just wondering about this as there are so many cheap micros out there, but what I need is an FPGA to play around with....

I'm busy googling right now, but I figured I'd throw this out there to you all to see if anyone knew anything off hand.

Thanks!

I guess you better define cheap. As a rule of thumb, the cost of an IC has to do with die size and number of package pins. The trend in FPGA is large packages with boatloads of pins. So I'm guessing the answer to your question is probably not.

I guess I'm asking if it's possible to do DIY breadboarding/soldering projects with FPGA's? Or are the package sizes always too many pins for that kind of thing, forcing you to get an eval board? I looked on Digikey and they have some non-stock FPGA's that are PLCC that are probably cheap (it said "call")...but I have no idea as to whether or not I could actually buy one hoping to breadboard it somehow (even if I used a microscope to solder). PLCC is 44 or 48 pins I think which is 1+ mm ....which sounds microscope solderable to me, but I've never done it so I don't know. What would be the smallest package I could get that is reasonably microscope solderable?

They do make "surfboards" for some SMD IC's.
Basically an FPGA/SOIC/etc. soldered onto a small board,with a bunch of pins sticking out of the bottom,like a DIP.

They seem to be kind of spendy though.

there are GAL's/PAL's (gate array and programmable array logic)

they don't off many gates though.

any of the CPLD/FPGA's will be more pricey, though atmel does have some form of FPGA in some of their micros. they may not be reprogrammable though.

for $300 you can get a spartan2 pro eval kit from digilent. not a bad price, and has all types of things to interface to -- RAM, XSGA, SATA, GigE, Flash cards, ect...


you may also like the cypress PSOC, which is a microcontroller with built in analog and digital periphrials. eg, A PSOC might have an 8 bit output bus combined with a dual 12bit ADC and 8bit DAC and 2 PWM channels and I2C port to something else. Its a neat product for the sub 100kHz world, having many analog and digital functions. still, one issue is the lack of a negative supply for analog ports. not that you can't find ways around it.

Yes it does seem to be getting on the pricey end. It's odd because when I started looking for microcontroller stuff it seemed there was plenty of stuff out there for DIY projects, but it seems harder to find stuff for FPGA's that isn't expensive. Not that eval boards are really pricey, but I'm just surprised there isn't more super cheap stuff like there is for micros. I'm still looking though.

BTW, thanks a lot for your input...can use all I can get!

Get a socket for PLCC packages. Should allow you to breadboard. Just don't expect very high frequent signals to come out right

CPLDs have lower gate density than FPGAs but are also cheaper & easier
to find in PLCC packages. XC95**XL from xilinx, for example. sell for 1-4 $
depending on # of cells & package.

FPGAs are almost always in QFP packages (when not BGA), so you really
need a breakout board or small kit. www.fpga4fun.com has a few cheap
boards to get you started.

an FPGA alone is 10$+ , with huge devices (Virtex, etc.) costing easily a
couple hundred $ by themselves!

Speaking of the XC95**XL; Digilent that were mentioned above have a Cmod module that apparently includes the XC9572XL, which has 72 macrocells and IIRC about 1600 gates. The module is in a 0.7" x 2.16" DIP module and has programming via JTAG. Digilent sells such cables for USB as well as parallel port.

I haven't tried them out myself but I've looked at them sometimes and wondered if they are any good. The price for a module is $17.95 so I guess they're decent. For simple breadboarding projects at least.

Mankku

Holy crap this is some good info...I knew you guys wouldn't let me down. After thinking about it further it seems I'd be best off finding simulation software and completing my code in order to determine my requirements. At the moment I still don't even know how many gates I need etc. But I'm told that the software can help me determine that....so I'll probably do that first. That fpga for fun site looks cool, though. I'm gonna keep googling and looking for other sites like that which can lead me in the right direction. Thanks for your help guys!

you should make sure your designs are synthesizable. you'll find that HDL languages will let you code an simulate things that would never actually work in actual HW. after that is trying to get things to run faster, and the tricks required.

and fighting with synthesis tools is definately a fun time.

good advice...will definitely keep that in mind....

You should also check out the supply voltage for the FPGA. Many of them is not made in 5V any more, only 3.3V and below. This is important for your interface to he chip.

TOK

kk, will do....

Both Xilinx and Altera allow a download of a free version of their SW suites. Great place to start. Write your design, synthesise for the component of your choice and see if it fits.