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I want to use an FPGA for my project and I want to use an FPGA as I want to implement the functionality of multiplexers within it.

Also I want to implement a microcontroller function within an FPGA. I know this is possible but just wanted to be sure about it in the case of low cost FPGAs.

I have the following questions:

  1. I also want to implement a Digital to Analog amplifier.

  2. I want to use 100 FPGAs and I want to know whether it is possible to have just a single programming board and program all these 100 FPGAs and then use them standalone in my PCB.

As FPGAs are cheap but the programming boards are very expensive.

  1. Also I was unable to find through-hole FPGAs, can someone tell me that what is the maximum pin count through hole FPGA I can find, if I can find one.

Thanks for your suggestions.

Kind Regards.

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closed as too broad by Tom Carpenter, Wesley Lee, ThreePhaseEel, uint128_t, DoxyLover Feb 21 '17 at 7:39

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

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    \$\begingroup\$ Really? Just, no. \$\endgroup\$ – Tom Carpenter Feb 20 '17 at 11:20
  • \$\begingroup\$ What is a "Digital to Analog amplifier"??? \$\endgroup\$ – Curd Feb 20 '17 at 11:25
  • \$\begingroup\$ Doesn't make any sense to me, sorry. \$\endgroup\$ – Enric Blanco Feb 20 '17 at 11:56
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through-hole FPGAs

I was going to say "there aren't any", but digikey surprised me: http://www.digikey.co.uk/product-detail/en/microsemi-corporation/APA600-CGS624M/APA600-CGS624M-ND/4294652

They're £4000 each, out of stock, and almost obsolete.

Realistically you'll have to use one of the surface mount QFP versions.

As FPGAs are cheap but the programming boards are very expensive.

Usually the other way round. In production, you'll have the FPGA "boot" off a small EEPROM. These are in the $1 cost range.

100 FPGAs in my PCB

What, on the same colossal PCB? Are you sure?

Digital to Analog amplifier

FPGA isn't the obvious choice for that project?

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  • \$\begingroup\$ Thanks for your reply. I am sorry for the DAC question, I read somewhere that there's a possibility to implement it. I have to use 100 FPGAs on 100 different PCBs, in short 1 FPGA per PCB and all the FPGAs will have the same function to perform. And if I understood your question correctly, then I can use an external EEPROM and then use an FPGA. For my project I have to use Muxs and need to control them through a microcontroller, need to apply certain voltage at the output pin of a mux. So I thought of using a single FPGA for performing both these tasks. Is it possible? \$\endgroup\$ – Samurai Feb 20 '17 at 11:28
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    \$\begingroup\$ It sounds like you're starting with a solution and trying to fit it to your problem. If you were to describe the context of what you were actually trying to build you might get better responses. \$\endgroup\$ – pjc50 Feb 20 '17 at 11:31
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    \$\begingroup\$ Controllable current? About how much current? FPGAs are not at all suitable for this - a digital mux replicates a logical value not an amount of current! You might be better off with regular transistors. (And you said "current" at one point and "voltage" at another. What's on the other end - what are you driving?) \$\endgroup\$ – pjc50 Feb 20 '17 at 11:39
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    \$\begingroup\$ So you want to apply a voltage to one pin while holding 49 others low and verify that on the other end you see that voltage on a single pin but no others. You then want to repeat this on each pin. Do I have that correct? If so get rid of the mux, use shift registers on each end. And there is no need for a processor of any sort, that is the sort of thing a logic state machine can do without the need for any processor. A small PLD for the state machine and two chains of shift registers, one for input, one for output and you're done. \$\endgroup\$ – Andrew Feb 20 '17 at 12:04
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    \$\begingroup\$ The flexibility of FPGA is really a cost here: if you're not familiar with shift registers, it'll take you months to get something working on an FPGA. \$\endgroup\$ – pjc50 Feb 20 '17 at 14:42
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Also I want to implement a microcontroller function within an FPGA. I know this is possible but just wanted to be sure about it in the case of low cost FPGAs.

It depends how complex the controller is going to be and how fast you want to run it. You pay for size and speed.

I also want to implement a Digital to Analog amplifier.

FPGAs are digital only.

I want to use 100 FPGAs and I want to know whether it is possible to have just a single programming board and program all these 100 FPGAs and then use them standalone in my PCB.

Most FPGAs are volatile, they lose their program when power is removed. They normally read their program from a serial ROM on power up or are programmed by a processor every time.

As FPGAs are cheap but the programming boards are very expensive.

That's an "alternative fact".

Also I was unable to find through-hole FPGAs

That's because such a thing is an odd idea. You use FPGAs when you need to fit a lot of logic into a small area. Why would you then use a massive through hold package when surface mount ones are so much smaller.

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  • \$\begingroup\$ A DAC can be implemented using an R-2R ladder and an op amp buffer. \$\endgroup\$ – Leon Heller Feb 20 '17 at 11:36
  • \$\begingroup\$ But in that situation all of the analog system is external to the FGPA, the FPGA remains a purely digital system. With external electronics you can create an analog signal from virtually any digital system. You could use a PWM output and an RC filter if you wanted. But how to get an analog signal from a digital system is a completely different question and unrelated to FPGAs. \$\endgroup\$ – Andrew Feb 20 '17 at 11:56

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