5V input COMPATIBLE ALTERA FPGA FAMILY

[Altera_Forum]

Can anyone suggest ALTERA fpga which has 5V compatible Input.

[Altera_Forum]

The old Flex 10K family were 5V devices. You'd be better off using something more recent with level converters.

[Altera_Forum]

--- Quote Start ---  The old Flex 10K family were 5V devices. You'd be better off using something more recent with level converters.  --- Quote End ---   I am giving synchronous clk and data...clk rate is 153.610kHZ.....do you think a level converter will help this without any deterioration in performance

[Altera_Forum]

--- Quote Start ---  I am giving synchronous clk and data...clk rate is 153.610kHZ.....do you think a level converter will help this without any deterioration in performance  --- Quote End ---    A period of a Kilohertz waveform is an eternity to modern FPGAs, you can use buffers like the TinyLogic and LittleLogic devices from Fairchild and TI, or if the signals are bidirectional and you don't have a direction control, use a bus switch. Fairchild, TI, NXP, Pericom, and others have parts. Just search on Digikey, and then read some data sheets. If you have questions, post them on the forum.  Cheers, Dave

[Altera_Forum]

Some of the X products had built-in clamping diodes which could sink 12mA or so from 5V down to 3.3V. This let you read 5V safely as long as you had a series resistor from your peripheral ic. You would still need a shifter to drive, if VOH's voltage was not high enough for the peripheral's VIH. 

 I'm curious if any of Altera's products have this feature.

[Altera_Forum]

--- Quote Start ---  Some of the X products had built-in clamping diodes which could sink 12mA or so from 5V down to 3.3V. This let you read 5V safely as long as you had a series resistor from your peripheral ic. You would still need a shifter to drive, if VOH's voltage was not high enough for the peripheral's VIH.  I'm curious if any of Altera's products have this feature.  --- Quote End ---    Some devices have a PCI clamping diode. However, if you're going to create a PCI board, and you implement hot-swap, you end up needing to use BusSwitch buffers with a 1V precharge, so you get 3.3V clamping for "free" by powering the BusSwitches appropriately.  All the handbooks for the latest generation devices indicate a 100% duty over-shoot of around 4.1V maximum. So none of the devices are 5V tolerant.  Cheers, Dave

[Altera_Forum]

Now whether if pin is configured as PCI I/O can I give 5V input (General Input) and will it not affect the performance of device or damage it.

[Altera_Forum]

--- Quote Start ---  Now whether if pin is configured as PCI I/O can I give 5V input (General Input) and will it not affect the performance of device or damage it.  --- Quote End ---   Read the data sheet or handbook for the device.  Most PCI clamping diodes are there to clamp overshoot, not a DC level.  If you know what device you are going to use, try to find the schematics for a PCI evaluation board that uses the device and see what they did.  Keep in mind that most PCI buses will in fact be 3.3V, so you may need to support both voltages. As I said earlier, this is where bus switches are useful, as it makes it easy to create a universal PCI board.  Cheers, Dave