Choosing a FPGA

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Hi,

I am new to FPGA. I am looking for a FPGA to do motor control. I have looked around the website and read a little about it. Could you please help me to find one?

The speed has to be more than 150MHz, single core processor, 12 pwm channels (synchronised), more than 17 ADC channels for different sensors, non BGA packaging, 2 SPI, 2 CAN and operating temperature between -55C and 105C (or more) and many GPIO (nearly 100)

I will very much appreciate your help.

Thank you,

Shiromini

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Well, that is a pretty complex set of required features, especially for a non-BGA package.

Altera MAX 10 series gets you close: 17 (or 18) A/D channels, EQFP144 package, -40'C to 125'C automotive grade. 101 I/Os in the EQFP package.

For processor, you would have to roll your own soft core. Ditto for PWM channels, 2xSPI, and 2xCAN. These would be implemented in device logic.

If you had to have a hard processor core (ie, ARM) then likely you would lose the BGA package and the integrated ADC options.

Hi

Thank you for your response. How many logic modules do I need for my purpose? What are logic modules? What are DSP blocks and memory blocks? How many do I need?

If you mean logic blocks, these are the basic logic elements in the chip - consisting of a LUT (to create the logic equations) and a register.

DSPs are basically multipliers

Memory blocks are self explanitory.

If you dont understand these, then you highly suggest you get learning about digital logic and how it works.

Only you can determin how many you need - you should be able to estimate DSP and Ram requirements from your algorithm.

Without understanding the basic elements, you have no chance choosing what board you need.

If you had simply googled "FPGA motor control" you would have found a vast amount help on this issue. Altera, for example, has a number of reference designs and IP to avoid reinventing the wheel. There are many devel boards usable for motor control. Get one and do a simple two axis design first (after figuring out how to make LED's blink). Your specs are far to vague for anyone to help you and once you firm them up, you can read the FPGA spec sheets as easily as anyone.

https://www.altera.com/solutions/industry/industrial/applications/automation/motor-control.html (https://www.altera.com/solutions/industry/industrial/applications/automation/motor-control.html)

I can almost guarantee you're going to have to prioritize your requirements and give up some things. Non-BGA (why?) and -55C? Unless your launching it into space, those may be the first that have to go.

Well, while this is a little bit off-Topic..

There are also other applications than only space ones requiring -55°C. From my Point of view everyone is more and more focussed on automotive or Extended industrial, both starting at -40°C ;-)

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Well, while this is a little bit off-Topic..

There are also other applications than only space ones requiring -55°C. From my Point of view everyone is more and more focussed on automotive or Extended industrial, both starting at -40°C ;-)

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I got a bit curious and temps less than -40°C are not all that uncommon in Alaska etc. But -55°C requires military grade and many chips are not available in it.

https://en.wikipedia.org/wiki/operating_temperature

Mechanical reliability of BGA concerns some applications. We've used BGA FPGA's for many years in an board that is subject to 3 or 4 G's a few hundred times and hour with no problem. But it's hardly an extreme case. There are ways to deal with the problem:

https://en.wikipedia.org/wiki/ball_grid_array#noncompliant_connections

I think he has alot of other issues before he needs to worry about such things though.