Intel® Quartus® Prime Standard Edition User Guide: Platform Designer

ID 683364
Date 12/15/2018
Public
Document Table of Contents

2.10.2. Multiplexer Examples

You can combine adapters with streaming components to create datapaths whose input and output streams have different properties. The following examples demonstrate datapaths in which the output stream exhibits higher performance than the input stream.

The diagram below illustrates a datapath that uses the dual clock version of the on-chip FIFO memory to boost the frequency of input data from 100 MHz to 110 MHz by sampling two input streams at differential rates. The on-chip FIFO memory has an input clock frequency of 100 MHz, and an output clock frequency of 110 MHz. The channel multiplexer runs at 110 MHz and samples one input stream 27.3 percent of the time, and the second 72.7 percent of the time. You must know what the typical and maximum input channel utilizations are before for this type of design. For example, if the first channel hits 50% utilization, the output stream exceeds 100% utilization.

Figure 76. Datapath that Doubles the Clock Frequency


The diagram below illustrates a datapath that uses a data format adapter and Avalon® -ST channel multiplexer to merge the 8-bit 100 MHz input from two streaming data sources into a single 16-bit 100 MHz streaming output. This example shows an output with double the throughput of each interface with a corresponding doubling of the data width.

Figure 77. Datapath to Double Data Width and Maintain Original Frequency


The diagram below illustrates a datapath that uses the dual clock version of the on-chip FIFO memory and Avalon® -ST channel multiplexer to merge the 100 MHz input from two streaming data sources into a single 200 MHz streaming output. This example shows an output with double the throughput of each interface with a corresponding doubling of the clock frequency.

Figure 78. Datapath to Boost the Clock Frequency