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Is it better to use DSP or FPGA ?

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bimbla

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DSP or FPGA

What is recommended between using a DSP or FPGA configured as DSP? Would the discussion be application specific or general?
Kindly give reasons for your opinions.

Thank you.

bimbla.
 

Jayson

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I've seen people mention that if you want a fast DSP then FPGA, if slow then regular DSP IC. However no one has ever explained why. I wonder if a slow DSP be done on an FPGA?

I've never been able to find any reference designs of implementing a DSP on an FPGA, though I'm sure some people have done these.

- Jayson
 

juripero

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If you want high performance, high clock rate, FPGA is a better choice. You can have for example many mulitpliers running in parallel, which will speed up your design.
 

System.out

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In a FPGA, one could build a adder tree in parallel so it could have better performace, as somebody said above, but thats only for integer operations. For floating point operation you would have a better performance with a DSP, also depends on what are your requirements is not the same cost for an FPGA than a DSP.

Cheers
 

paviljonac

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Re: DSP or FPGA

there is a trend to use so called "soft processor cores" lately. these are optimized FPGA cores, used for decision-oriented tasks within system on reconfigurable chip... as i know, DSP cores in the terms of rough definition of DSPs as "CPU with multiplier"... are not available!?
 

pineapple

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Re: DSP or FPGA

Depends on you want a general purpose DSP or just an ASIC chip. DSP way has much more software support. FPGA you are on you own.
 

jacklalo020

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Re: DSP or FPGA

Hi,
This is basicly a simple and hard question at the same time. I took a course about Programmable logic and VLSI design and what i retine is that it depends on the timing you want to achieve, the time to market, and the quantity you are going to sale.
For simple application that doesn't need a high frequency rate, it's better for you to use DSP, but if the time is crucial, you have to work with FPGA. it was simple some years ago to give a response about the choice between FPGA and ASIC, but with the high complexity and density of the latest version of FPGA it becom harder :( FPGA is well suitable for prototyping, and when you meet your goals, and if you are sure to sale a great quatity of your chip you can go for ASIC because you are going to amortize the fees for the masks design ( some millions of US dollars :) )
Hope it is clear, the response as i told is not easy to give
 

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ydao

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DSP or FPGA

Implement with FPGA is hardware based and implement with DSP IC is software based. Hardware implement take advantage of speed and with disadvantage of cost.
 

Al Farouk

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Re: DSP or FPGA

I read many articles compare between ASIC and DSP, the main items was
1- Flexibility and reconfiguration: DSP wen
2- Speed : ASIC wen
3- Area : almost equal as the area saved by multifuntional DSP core is wasted by memroy area required by DSP.
4- reuse: DSP the same core do many function but each block in ASIC if not used it will be area wast, but ASIC school reply that due to high densities of new technology that will not harm.

if we put into consideration that FPGA generally is a step lower ASIC then DSP will preferred as general regarding speed and flexibility. but if others fctors as cost, design funtion,...etc the decision will differ.
 

speedoak

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Re: DSP or FPGA

the biggest difficultiy of FPGA DSP design is, the DSP engineer usually know very little about FPGA, and FPGA designer knows little about DSP algorithm, they live in the different world.
as long as programmable DSP become more and more powerful, I think the future archtecture of DSP will be programmable DSP plus DSP-co-processor, which is implemented in FPGA
 

eltonjohn

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Re: DSP or FPGA

I do agree with the last participant . There is a well know courbe of DSP processing power needed in the next few years . unfurtunatly in telecomunications for example the standarts DSP cpu based systems lack of the power required .The DSP FPGA methodologies in the other side are developing very fast ..Today the research is focused on RECONFIGURABLE systems .. this are processors that wil be able to change their architecure in function of the algorithm requirements .
There are new cpus that don't look like normal DSP cpus neither PROGRAMABLE logic (FPGA).. So a new field of reconfigurable logic is taking shape .But yes i see a lot of SOFTWARE tools and harware boards coupling XILINX parts and TI dps now avalaible .. I won't be surprised to see a VIRTEX III with a C6000 FLOATING POINT dps core . it would be the normal evolution of this field!
 

Usman Hai

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Re: DSP or FPGA

If u r interested in DSP of larger I/O ports then go towards FPGA
or if u want complex algo implemnetation then go for DSP boards.

Usman Hai
Pakistan
 

ahsan

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DSP or FPGA

If your aim is signal processing like filtering a signal, performing certain algo....DSP are better than FPGA. In DSP you have better software support than FPGA. If you want to use a device for control , parallel, fast processing than FPGA are better choice.
 

llrry

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DSP or FPGA

well, many design embed a DSP core into FPGA, since we can get an excellent system architecture
with a optimized balance between HW and SW.
 

ashishjindal76

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DSP or FPGA

Hi folks

Accoding to me it depends which one is better. the latest Fpga have the capability to have multiple processors to be initiated on a single fpga which makes it extremly fast and very high throughput with cheaper cost which is not possible in the stand alone dsp processor. in fpga the dsp processor used r the softcores not the physical processors.

regards
ashish
 

lpllong

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Re: DSP or FPGA

I think choosing DSP or FPGA depends on the project!
 

cawan

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DSP or FPGA

I think the key point of DSP implementation in FPGA is the design of DSP algorithm that suit the FPGA architecture. For example, it is better to make a design with 2^n taps instead of a strange odd number of taps. The architecture of LUT need to be consider in details. Of course, it is easier to establish an algorithm in DSP, with nice tuned pipelining, optimized, but the development trend to re-configurable device, it is good to apply FPGA as new DSP platform.
 

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ydao

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DSP or FPGA

I think the key point of DSP implementation in FPGA is the design is whether you have the IP core and how much effort you need to develop it.
 

Aser

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Re: DSP or FPGA

The following was not mentioned.
1. FPGA provide calculations with any needed data width.
This provides additional speed and/or precision.
In DSP usually you have to do with 16 bits,
therefore problems occur with data scaling, rounding, shifting, double precision, underloading when pixel computing, etc.
2.FPGA provides the very high speed logic to solve decision or logic problems.
DSP makes 2-way decision with a single logic instruction, 4-way decision - more than 3 instructions, etc.
3. One FPGA with 1000 pads can substitute tenths of DSPs with much less pins, if the project affords many IOs.
 

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