xilinx xc 3000
TRANSCRIPT
Seminar On:-Xilinx xc 3000 yogesh s. watile Sub:MDS-1 M-tech I Sem.(VLSI)
XC3000-Series Field Programmable Gate Arrays (FPGAs) provide a group of high-performance, high-density, digital integrated circuits. Their regular, extendable, flexible, user-programmable array architecture is composed of a configuration program store plus three types of configurable elements: I/O Blocks (IOBs), Configurable Logic Bocks (CLBs) and resources for interconnection. The XC3000 Field Programmable Gate Array families provide a variety of logic capacities, package styles, temperature ranges and speed grades.
Xilinx FPGAs - Generic Features
High Performance at different voltages Footprint Compatibility - Devices within each family are compatible. Low power consumption/high performance Integrated Software
XC2000
First FPGA Family from Xilinx. Two members: XC2064 1000 Gates XC2018 1500 Gates Ext. Crystal Oscillator. No Tri State Buffers. XACT 1.0 Development System.
Advantages of XC3000 over xc2000
Replaces TTL, MSI and other PLD logics. Integrates complete subsystem into single Package. System clock Speed up to 50 MHz. On-chip crystal Oscillator. Over 20 different Packaging Options.
XC3000
Series of FPGA devices:
XC3000A Family XC3000L Family XC3100A Family XC3100L Family
Fig. Layout of part of a programmable logic cell array
Fig. Configuration Memory cell
The static memory cell used for the configuration memory in the Field Programmable Gate Array has been designed specifically for high reliability and noise immunity the basic memory cell consists of two CMOS inverters plus a pass transistor used for writing and reading cell data.
Xilinx XC3000 CLBA 32-bit look-up table ( LUT ) CLB propagation delay is fixed (the LUT access time) and independent of the logic function 7 inputs to the XC3000 CLB:
y 5 CLB inputs (AE), and y 2 flip-flop outputs (QX and QY)
2 outputs from the LUT (F and G). Since a 32-bit LUT requires only five variables to form a unique address (32 = 25), there are multiple ways to use the LUT
Xilinx XC3000 CLB
Use 5 of the 7 possible inputs (AE, QX, QY) with the entire 32-bit LUTy the CLB outputs (F and G) are then identical
Split the 32-bit LUT in half to implement 2 functions of 4 variables eachy choose 4 input variables from the 7 inputs (AE, QX, QY). y you have to choose 2 of the inputs from the 5 CLB inputs (A
E); then one function output connects to F and the other output connects to G
You can split the 32-bit LUT in half, using one of the 7 input variables as a select input to a 2:1 MUX that switches between F and Gy to implement some functions of 6 and 7 variables
Xilinx XC3000 CLB
The block diagram for an XC3000 family CLB illustrates all of these features To simplify the diagram, programmable MUX select lines are not shown Combinational function is a LUT
LUT
XC3000 CLB
Fig. Combinatorial Logic options
(A) Combinatorial Logic Option FG generates two functions of four variables each. One variable, A, must be common to both functions. The second and third variable can be any choice of B, C, QX and QY. The fourth variable can be any choice of D or E. (B). Combinatorial Logic Option F generates any function of five variables: A, D, E and two choices out of B, C, QX, QY. (C). Combinatorial Logic Option FGM allows variable E to select between two functions of four variables: Both have common inputs A and D and any choice out of B, C, QX and QY for the remaining two variables. Option 3 can then implement some functions of six or seven variables.
Fig. Xilinx 3000 series I/O block
Programmable interconnects:
General purpose interconnects
Direct interconnect between adjacent CLBs
Long line
Fig: General purpose interconnects
Direct interconnects between adjacent CLBs
Vertical and horizontal long lines:
Crystal oscillator: