# Synthesis rtl. Logic synthesis - wikipedia

The applications for logic synthesis lay primarily in digital computer design. Circuits such as a binary multiplier or a binary adder are examples of more complex binary operations that can be implemented using basic logic operators.

High-level synthesis With a goal of increasing designer productivity, research efforts on the synthesis of circuits specified at the behavioral level have led to the emergence of commercial solutions in[3] which are used for complex ASIC and FPGA design.

As of latethere was an emerging adoption in the United States. Logic design is commonly followed by the circuit design step.

## Yosys Open SYnthesis Suite :: About

Process stages[ edit ] The high-level synthesis process consists of a number of activities. Logic elements[ edit ] Logic design is a step in the standard design cycle in which the functional design of an electronic circuit is converted into the representation which captures logic operationsarithmetic operationscontrol flowetc.

This bit-accurate specification makes the high level synthesis source specification functionally complete. The Karnaugh map-based minimization of logic is guided by a set of rules on how entries in the maps can be combined. Within a decade, the technology migrated to commercial logic synthesis products offered by electronic design automation companies.

Next, this network is optimized using several technology-independent techniques before technology-dependent optimizations are performed. History[ edit ] Early academic work extracted scheduling, allocation, and binding as the basic steps for high-level-synthesis.

It used local transformations to simplify logic.

Scheduling partitions the algorithm in control steps that are used to define the states in the finite-state machine. In the early days, logic design involved manipulating the truth table representations as Karnaugh maps.

Finally, technology-dependent optimization transforms the technology-independent circuit into a network of gates in a given technology. Allocation and binding maps the instructions and variables Synthesis rtl the hardware components, multiplexers, registers and wires of the data path.

## Navigation menu

This language shift, combined with other technical advances was a key enabler for successful industrial usage. This exact minimization technique presented the notion of prime implicants and minimum cost covers that would become the cornerstone of two-level minimization.

The simple cost estimates are replaced by more concrete, implementation-driven estimates during and after technology mapping. Starting from an RTL description of a design, the synthesis tool constructs a corresponding multilevel Boolean network. InClaude Shannon showed that the two-valued Boolean algebra can describe the operation of switching circuits.

Mapping is constrained by factors such as the available gates logic functions in the technology library, the drive sizes for each gate, and the delay, powerand area characteristics of each gate.

A human designer can typically only work with Karnaugh maps containing up to four to six variables. High-level synthesis was primarily adopted in Japan and Europe in the early years.

The abstraction level used was partially timed clocked processes.

## Cadence Online Support

In modern electronic Abortion research paper topic sentence automation parts of the logical design may be automated using high-level synthesis tools based on the behavioral description of the circuit.

Some high-level synthesis tools combine some of these activities or perform them iteratively to converge on the desired solution.

High-level synthesis or behavioral synthesis[ edit ] Main article: The evolution from discrete logic components to programmable logic arrays PLAs hastened the need for efficient two-level minimization, since minimizing terms in a two-level representation reduces the area in a PLA.

Logic optimization and Circuit minimization Typical practical implementations of a logic function utilize a multi-level network of logic elements. Each control step contains one small section of the algorithm that can be performed in a single clock cycle in the hardware.

The refinement requires additional information on the level of quantization noise that can be tolerated, the valid input ranges etc. Arithmetic operations are usually implemented with the use of logic operators.

High-level synthesis typically also includes a bit-accurate executable specification as input, since to derive an efficient hardware implementation, additional information is needed on what is an acceptable Mean-Square Error or Bit-Error Rate etc.

For example, if the designer starts with an FIR filter written using the "double" floating type, before he or she can derive an efficient hardware implementation, they need to perform numerical refinement to arrive at a fixed-point implementation.

The typical cost function during technology-independent optimizations is total literal count of the factored representation of the logic function which correlates quite well with circuit area. A common output of this step is RTL description.