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I am designing a circuit for an electronic coil winder. It has a few binary counters, equality detectors, 7 segment decoders and flip flops.

How it is possible to get all of this logic onto 1 programmable chip without resorting to totally retro technology?

Is there something like a GAL that can is well supported for programming on a modern computer?

I can easily make it from standard CMOS or TTL chips, but it would be a good learning opportunity to try programming my own logic.

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    \$\begingroup\$ Why would you want to even implement that with logic ? Do you need a very high speed ? I don't think so. Why not simply use a microcontroller. Then you program the behavior you need. Sure it sounds silly to use a software solution to make a simple logic function. But it is easier and more flexible. \$\endgroup\$
    – Bimpelrekkie
    Commented Apr 7, 2017 at 9:52
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    \$\begingroup\$ I am already familiar with building logic circuits, and I would like to learn how to do it because I may be able to use those skills to do other projects. I am more comfortable with hard wired circuit design than I am with sequential programming. I can see why other people would use a microcontroller. \$\endgroup\$
    – John Spence
    Commented Apr 7, 2017 at 11:27
  • \$\begingroup\$ CPLD is the acronym for 'small' FPGAs, custom programmable logic device. Lattice as mentioned in the answer below is probably the best source to start looking at these. But really, PIC or Arduino would be the place that 999/1000 engineers (possible under estimate here) would start for your specific (very low speed) application. \$\endgroup\$
    – Neil_UK
    Commented Apr 7, 2017 at 11:34
  • \$\begingroup\$ Hi there @Neil_UK, interesting your '999/1000' engineers would use an MCU - I've seen the total opposite :-) Few people in the companies I've been in choose an MCU for a logic job, nor more than they'd use an op-amp as a voltage regulator...it's possible but the wrong tool. I've used both some I'm very agnostic. It sounds like it's just your personal experience, though I imagine you've not worked with several thousand engineers :-) , and I can only speaking from mine, obviously. For price, support but more simplicity and failure mode, seems crazy to me and I understand the counter-arguments. \$\endgroup\$
    – TonyM
    Commented Apr 9, 2017 at 9:51
  • \$\begingroup\$ @TonyM 999/1000 was intended to be provocative, and of course it's a figure PDOOMA. I think my comment was swayed my last most recent employer where we sprinkled Arduinos around like Smarties for custom test gear, though the product itself used a micropower TI MCU/radio. Whenever we talked about a homer that we were doing, it was usually Arduino based. \$\endgroup\$
    – Neil_UK
    Commented Apr 9, 2017 at 10:21

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The modern way to do such a digital logic circuit would be in an FPGA or CPLD.

The way I'd recommend for your particular logic circuit is a CPLD. Have a look at the Altera MAX10 family or the Lattic iCE40 devices. You can buy a cheap demo' board like the iCEStick, download the free development tools and get something up to experiment with at home or work.

You will have to learn VHDL (my preference) or Verilog but that's part of the learning you mentioned you're interested in doing.

You could use a microcontroller to produce a similar result but by a quite different function...but it doesn't address your question. And you'd have to learn to programme that so there's work either way.

(I know Lattice call iCE40 an FPGA family, but across the logic chips market, they have more in common with CPLDs. The name will do for the purpose here.)

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  • \$\begingroup\$ Just a quick comment: ice40 was maybe ten years ago. Bow lattice mainstream is MachXO2, which is my preference, actually for that stuff. Altera's Max10 would also have internal ADC, but quartus somehow became less friendly than diamond... \$\endgroup\$
    – user76844
    Commented Apr 9, 2017 at 16:49
  • \$\begingroup\$ Hi @GregoryKornblum, thanks for the comment. In advocating these devices I went on popularity and sales costs from the distributors. Always found Quartus the most newcomer-friendly of all of them. Good recommendation for the MachX02. \$\endgroup\$
    – TonyM
    Commented Apr 9, 2017 at 17:07
  • \$\begingroup\$ I happen to use both. Frankly, you can tell Altera doesn't consider MAX10 very important. MachXO2 performs much better. \$\endgroup\$
    – user76844
    Commented Apr 9, 2017 at 17:13
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Microcontrollers are the modern way, but if you have reasons to avoid them (safety, or you don't know C), you need to use low cost FPGA, from either altera (now intel), xilinx, lattice or microsemi.

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  • \$\begingroup\$ So are there any small FPGAs with less than 1000 gates? \$\endgroup\$
    – John Spence
    Commented Apr 7, 2017 at 11:31
  • \$\begingroup\$ I doubt it. They count LUTs, which is equivalent of maybe 10-20 gates, so smallest have several hundreds of them. Byt they only cost a little more than microcontrollers \$\endgroup\$
    – user76844
    Commented Apr 7, 2017 at 11:33
  • \$\begingroup\$ By the way. Although there is usually a way to actually design FPGA gate by gate, it's absolutely not recommended. Normally people use VHDL or (the sick people among us) verilog. This is way more efficient for designs larger than 10-20 gates \$\endgroup\$
    – user76844
    Commented Apr 7, 2017 at 11:39
  • \$\begingroup\$ I notice that Xilinx and Altera offer visual schematic programming options. Xilinx has ISE and Altera has Quartus. They look more easy than to use than a text based environment. \$\endgroup\$
    – John Spence
    Commented Apr 7, 2017 at 12:50
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    \$\begingroup\$ I am afraid, learning all of those is too much of effort. Again, for short term go with what is easy and natural for you, for longer term- VHDL or verilog. \$\endgroup\$
    – user76844
    Commented Apr 7, 2017 at 13:28
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Actually, a new device has just come to market:

https://www.dialog-semiconductor.com/products/greenpak

It is the GreenPack series from Dialog semiconductor. You can implement most of the logic from discrete chips inside them, include custom LUTs, some of them also incorporate ADCs so you can perform analog functions, etc.

They are available from distributors pretty cheap, about 0.42€@100:

https://www.mouser.es/ProductDetail/Dialog-Semiconductor/SLG46620G?qs=%252B6g0mu59x7KnBmBQ6c05jQ%3D%3D

Hope you find this useful.

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  • \$\begingroup\$ Renesas (nee Silego, nee Dialog) Greenpak has been around for a while, at least since 2010. I've used them in several products. \$\endgroup\$
    – hacktastical
    Commented Jan 3 at 0:50
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Adding to TonyM's answer:

If you just want some programmable logic and don't want a sequential processor (a micro controller), here's a tiny iCE40 chip:

http://www.mouser.com/ProductDetail/Lattice/ICE40UL1K-SWG16ITR50/?qs=XJu%252bLGjWfSDdbhkO3WpKug%3D%3D

There are also parts like this that give you little logic blocks to work with: http://www.ti.com/product/cd4048b

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