01-08-2017 08:29 PM
Currently we are using XC95288XL-10PQG208C in our medical instrument. But due to hardware redesign we are planning to shift advanced series CPLD having more I/O pins.
Please let us know which options we can consider for design.
01-08-2017 09:15 PM
Do you need 5V compatibility? If not, the CoolRunner II XC2C512 comes in a BGA324 package with 270 I/O pins (your current chip has 168).
01-08-2017 09:27 PM
01-08-2017 10:19 PM
Our existing XC95288XL-10PQG208C is operating at 3.3V , Do you mean to say 5V tolerant pins? ( if so no such criteria )
01-08-2017 10:29 PM
Yes, that's what I meant. The XC95288XL tolerates 5V inputs, the CoolRunner II does not. Based on what you've said, it sounds like a CoolRunner II will do the job nicely.
If you only need a few more I/Os, then an XC2C256 in the 256-ball BGA package might work well (184 I/O). The next big step up is the XC2C384 in the 324-ball package (240 I/O), and then the biggest is the XC2C512 mentioned above (270 I/O).
01-09-2017 01:42 AM
I rechecked in design and found few 5V pins assigned to CPLD (Input pins), Is there any other options having more pins and has 5v tolerant pins.?
01-09-2017 03:24 AM
None that I'm aware of - at least none that are reasonably modern and therefore might have some useful life remaining. There were BGA versions of the XC95288XL with a few more I/O pins than the PQ208 version, but designing a new product around those now would be a very bad idea.
If it's just a few pins, you could fit a level shifter in there. For low-speed signals even a resistor voltage divider will be fine. You'll need a new PCB anyway for the new chip, and adding level translation there shouldn't be too hard.
Of course, the other option is to take advantage of the hardware redesign to eliminate 5V devices (and possibly a lot of other stuff) from the system. For example, if the 5V device is a processor, you could replace the processor and the CPLD with a Zynq 7010 - which will have orders or magnitude more processing power and more programmable logic than the original hardware, at a fraction of the power. If the 5V device is a sensor, it's likely that you can buy a modern sensor that provides better accuracy at a lower cost, while interfacing at 1.8V or 3.3V.
01-09-2017 04:13 AM
It has almost 84 Input pins and hard speed design including parallel ADC, sensing circuit. Hardware is rally complicated since it is biomedical instrument with many peripherals and PC104 board incorporated for LPT,TTL RGB LCD, Mouse etc.. Including level translator will add many lever shifting IC's and impact overall board size.
Is using resistor and diode to clamp voltage as mentioned in below app note is better option?
01-10-2017 12:42 AM
Also, is there any IC in QFP package having more that 200 GPIO pins, in any of mentioned CoolRunner series xilinx?
01-10-2017 12:59 AM - edited 01-10-2017 01:01 AM
01-10-2017 02:52 AM
Thanks for your reply.
Can you recommend level shifting techniques from 5V to 3.3V (Input to Xilinx) especially considering High Speed Design and complex hardware design?
Also please suggest for app notes for CPLD coolrunner schematics design/pcb layout guidelines.
01-10-2017 03:26 AM
01-10-2017 05:14 PM
There's no CoolRunner with that many I/O pins in a QFP package. The only CPLD of any sort I can find that meets your requirements is the Altera MAX 9000 (in a massive 40*40mm QFP304 package) that has 216 I/O pins, but it's obsolete and therefore definitely not a good idea for new designs. On the FPGA side, Microsemi will sell you an APA1000 with 248 I/O, in a 75*75mm QFP352 package (easily the largest package I've ever heard of for a single IC).
TI does a range of high-speed buffer chips that'll handle level conversion. Resistor-diode termination should work fine too; the big advantage of the TI chips is that you have one big chip to solder rather than 100+ tiny 0402 resistors and diodes.
01-19-2017 12:26 AM
For P/N: XC2C384-10FGG324I (CoolRunner II)
What are below pins...
GTS, GSR, GCK, CDRST, DGE
Can I left it floating, what is min circuit required for programming?
01-19-2017 12:52 AM
@yogesh Check this Datasheet for information on the Pin you looking for
01-19-2017 01:36 AM