Significantly increased system performance, higher capacity, and novel architectural characteristics, particularly Select-RAM memory, are the main benefits of XC4000X devices. Numerous additional routing features are also available with the XC4000X devices, such as unique high-speed clock buffers that can be used to quickly capture input data.
The related XC4000 device is pinout and bitstream compatible with any XC4000E device. An XC4000E device can be programmed using an existing XC4000 bitstream. An XC4000E bitstream cannot be put into an XC4000 device due to the XC4000E's several new features.
The corresponding array size devices in the XC4000 or XC4000E families are not bitstream compatible with the XC4000X Series devices. The XC4025, XC4025E, XC4028EX, and XC4028XL are examples of devices with an equivalent array size that are pinout compatible.
