参数资料
型号: EP20K400E
厂商: Altera Corporation
英文描述: Programmable Logic Device Family
中文描述: 可编程逻辑器件系列
文件页数: 16/117页
文件大小: 570K
代理商: EP20K400E
16
Altera Corporation
APEX 20K Programmable Logic Device Family Data Sheet
Cascade Chain
With the cascade chain, the APEX 20K architecture can implement
functions with a very wide fan-in. Adjacent LUTs can compute portions
of a function in parallel; the cascade chain serially connects the
intermediate values. The cascade chain can use a logical
AND
or logical
OR
(via De Morgan’s inversion) to connect the outputs of adjacent LEs. Each
additional LE provides four more inputs to the effective width of a
function, with a short cascade delay. Cascade chain logic can be created
automatically by the Quartus II software Compiler during design
processing, or manually by the designer during design entry.
Cascade chains longer than ten LEs are implemented automatically by
linking LABs together. For enhanced fitting, a long cascade chain skips
alternate LABs in a MegaLAB structure. A cascade chain longer than one
LAB skips either from an even-numbered LAB to the next even-numbered
LAB, or from an odd-numbered LAB to the next odd-numbered LAB. For
example, the last LE of the first LAB in the upper-left MegaLAB structure
carries to the first LE of the third LAB in the MegaLAB structure.
Figure 7
shows how the cascade function can connect adjacent LEs to form
functions with a wide fan-in.
Figure 7. APEX 20K Cascade Chain
LE1
LUT
LE2
LUT
d[3..0]
d[7..4]
d[(4n – 1)..(4n – 4)]
d[3..0]
d[7..4]
LEn
LE1
LE2
LEn
LUT
LUT
LUT
LUT
AND Cascade Chain
OR Cascade Chain
d[(4n – 1)..(4n – 4)]
相关PDF资料
PDF描述
EP20K600E Programmable Logic Device Family
EP20K60E Programmable Logic Device Family
EP220 Classic EPLDs
EP220-10 Classic EPLDs
EP220-10A Classic EPLDs
相关代理商/技术参数
参数描述
EP20K400EBC652-1 功能描述:FPGA - 现场可编程门阵列 CPLD - APEX 20K 1664 Macros 488 IO RoHS:否 制造商:Altera Corporation 系列:Cyclone V E 栅极数量: 逻辑块数量:943 内嵌式块RAM - EBR:1956 kbit 输入/输出端数量:128 最大工作频率:800 MHz 工作电源电压:1.1 V 最大工作温度:+ 70 C 安装风格:SMD/SMT 封装 / 箱体:FBGA-256
EP20K400EBC652-1ES 制造商:未知厂家 制造商全称:未知厂家 功能描述:FPGA
EP20K400EBC652-1N 功能描述:FPGA - 现场可编程门阵列 CPLD - APEX 20K 1664 Macros 488 IO RoHS:否 制造商:Altera Corporation 系列:Cyclone V E 栅极数量: 逻辑块数量:943 内嵌式块RAM - EBR:1956 kbit 输入/输出端数量:128 最大工作频率:800 MHz 工作电源电压:1.1 V 最大工作温度:+ 70 C 安装风格:SMD/SMT 封装 / 箱体:FBGA-256
EP20K400EBC652-1X 功能描述:FPGA - 现场可编程门阵列 CPLD - APEX 20K 1664 Macros 488 IO RoHS:否 制造商:Altera Corporation 系列:Cyclone V E 栅极数量: 逻辑块数量:943 内嵌式块RAM - EBR:1956 kbit 输入/输出端数量:128 最大工作频率:800 MHz 工作电源电压:1.1 V 最大工作温度:+ 70 C 安装风格:SMD/SMT 封装 / 箱体:FBGA-256
EP20K400EBC652-2 功能描述:FPGA - 现场可编程门阵列 CPLD - APEX 20K 1664 Macros 488 IO RoHS:否 制造商:Altera Corporation 系列:Cyclone V E 栅极数量: 逻辑块数量:943 内嵌式块RAM - EBR:1956 kbit 输入/输出端数量:128 最大工作频率:800 MHz 工作电源电压:1.1 V 最大工作温度:+ 70 C 安装风格:SMD/SMT 封装 / 箱体:FBGA-256