Configurable Logic Block

Versal ACAP Technical Reference Manual (AM011)

Document ID
AM011
Release Date
2022-04-26
Revision
1.4 English

The configurable logic block (CLB) includes logic and look-up tables (LUTs) that can be configured into many different combinations and connected to other components in the PL to create special purpose functions, processing units, and other entities.

Every CLB contains 32 LUTs and 64 flip-flops. The LUTs can be configured as either one 6-input LUT with one output, or as two 5-input LUTs with separate outputs but common inputs. Each LUT output can optionally be registered in a flip-flop.

In addition to the LUTs and flip-flops, the CLB contains arithmetic carry logic and multiplexers to create wider logic functions. Within each CLB, 16 LUTs can be configured as 64-bit RAM, 32-bit shift registers (SRL32), or two SRL16s.

Within every CLB are dedicated interconnect paths for connecting LUTs without having to exit and re-enter a CLB, drastically reducing the use of global routing resources. In addition, new CLB features such as cascade multiplexers allow flexible carry logic structures to be created.

For more information, see the Versal ACAP Configurable Logic Block Architecture Manual (AM005).