CIC Intel® FPGA IP: User Guide

Download PDF
ID 683246
Date 9/30/2019
Public
Document Table of Contents
Document Table of Contents x
1. About the CIC Intel® FPGA IP 2. CIC Intel® FPGA IP Getting Started 3. CIC Intel® FPGA IP Functional Description 4. CIC Intel® FPGA IP User Guide Document Archives 5. CIC Intel® FPGA IP User Guide Document Revision History
1. About the CIC Intel® FPGA IP x
1.1. DSP Intel® FPGA IP Features 1.2. CIC Intel® FPGA IP Features 1.3. DSP Intel® FPGA IP Device Family Support 1.4. DSP Intel® FPGA IP Verification 1.5. CIC Intel® FPGA IP Release Information 1.6. CIC Intel® FPGA IP Performance and Resource Utilization
2. CIC Intel® FPGA IP Getting Started x
2.1. Installing and Licensing Intel® FPGA IP Cores 2.2. IP Catalog and Parameter Editor 2.3. Generating IP Cores ( Intel® Quartus® Prime Pro Edition) 2.4. Simulating Intel® FPGA IP Cores 2.5. DSP Builder for Intel® FPGAs Design Flow
2.1. Installing and Licensing Intel® FPGA IP Cores x
2.1.1. Intel® FPGA IP Evaluation Mode 2.1.2. CIC IP Core Intel® FPGA IP Evaluation Mode Timeout Behavior
2.3. Generating IP Cores ( Intel® Quartus® Prime Pro Edition) x
2.3.1. IP Core Generation Output ( Intel® Quartus® Prime Pro Edition)
3. CIC Intel® FPGA IP Functional Description x
3.1. Variable Rate Change Factors 3.2. Multichannel Support 3.3. CIC Output Options 3.4. FIR Filter Compensation Coefficients 3.5. CIC Intel® FPGA IP Parameters 3.6. CIC Intel® FPGA IP Interfaces and Signals
3.2. Multichannel Support x
3.2.1. Multiple Input Single Output (MISO) 3.2.2. Single Input Multiple Output (SIMO)
3.3. CIC Output Options x
3.3.1. Output Data Width 3.3.2. Output Rounding 3.3.3. Hogenauer Pruning
3.6. CIC Intel® FPGA IP Interfaces and Signals x
3.6.1. Avalon Streaming Interfaces in DSP Intel FPGA IP 3.6.2. CIC Intel® FPGA IP Signals 3.6.3. Avalon Streaming Interface Data Transfer Timing 3.6.4. Packet Data Transfers
1. About the CIC Intel® FPGA IP
2. CIC Intel® FPGA IP Getting Started
3. CIC Intel® FPGA IP Functional Description
4. CIC Intel® FPGA IP User Guide Document Archives
5. CIC Intel® FPGA IP User Guide Document Revision History

3.3.2. Output Rounding

For high rate change factors, the maximum required data width for no data loss is large for many practical cases. To reduce the output data width to the input level, apply quantization at the end of the output stage. the CIC filter offers various rounding or saturation options. You can only apply these rounding options to the output stage of the filter. The data widths at the intermediate stages are not changed.
Table 6.  Output Rounding Options
Option Description
Truncation The CIC drops the LSBs. (Equivalent to rounding to minus infinity.)
Convergent rounding Also known as unbiased rounding. Rounds to the nearest even number. If the most significant deleted bit is one, and either the least significant of the remaining bits or at least one of the other deleted bits is one, then one is added to the remaining bits.
Round up Also known as rounding to plus infinity. Adds the MSB of the discarded bits for positive and negative numbers via the carry in.
Saturation Puts a limit value (upper limit in the case of overflow, or lower limit in the case of negative overflow) at the output when the input exceeds the allowed range. The upper limit is +2n-1 and lower limit is –2n
Level Two Title