Gate equivalent

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A gate equivalent (GE) stands for a unit of measure which allows specifying manufacturing-technology-independent complexity of digital electronic circuits. For today's CMOS technologies, the silicon area of a two-input drive-strength-one NAND gate usually constitutes the technology-dependent unit area commonly referred to as gate equivalent. A specification in gate equivalents for a certain circuit reflects a complexity measure, from which a corresponding silicon area can be deduced for a dedicated manufacturing technology.

In digital circuit design, a dedicated standard cell library is employed for each manufacturing technology (e.g., CMOS). The standard cell library comprises many different logic gates, for example a NAND gate. For each logical type of logic gate, e.g., a two-input NAND, there usually exist different physical realizations in the standard cell library, for instance with different output drive strengths.

Basically, a two-input drive-strength-one NAND gate in CMOS technology consists of four transistors.

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Field-programmable gate array Array of logic gates that are reprogrammable

A field-programmable gate array (FPGA) is an integrated circuit designed to be configured by a customer or a designer after manufacturing – hence the term field-programmable. The FPGA configuration is generally specified using a hardware description language (HDL), similar to that used for an application-specific integrated circuit (ASIC). Circuit diagrams were previously used to specify the configuration, but this is increasingly rare due to the advent of electronic design automation tools.

Integrated circuit Electronic circuit formed on a small, flat piece of semiconductor material

An integrated circuit or monolithic integrated circuit is a set of electronic circuits on one small flat piece of semiconductor material, usually silicon. Large numbers of tiny MOSFETs integrate into a small chip. This results in circuits that are orders of magnitude smaller, faster, and less expensive than those constructed of discrete electronic components. The IC's mass production capability, reliability, and building-block approach to integrated circuit design has ensured the rapid adoption of standardized ICs in place of designs using discrete transistors. ICs are now used in virtually all electronic equipment and have revolutionized the world of electronics. Computers, mobile phones, and other digital home appliances are now inextricable parts of the structure of modern societies, made possible by the small size and low cost of ICs such as modern computer processors and microcontrollers.

A logic gate is an idealized model of computation or physical electronic device implementing a Boolean function, a logical operation performed on one or more binary inputs that produces a single binary output. Depending on the context, the term may refer to an ideal logic gate, one that has for instance zero rise time and unlimited fan-out, or it may refer to a non-ideal physical device.

Digital electronics Electronic circuits that utilize digital signals

Digital electronics is a field of electronics involving the study of digital signals and the engineering of devices that use or produce them. This is in contrast to analog electronics and analog signals.

Transistor–transistor logic (TTL) is a logic family built from bipolar junction transistors. Its name signifies that transistors perform both the logic function and the amplifying function, as opposed to resistor–transistor logic (RTL) or diode–transistor logic (DTL).

CMOS Technology for constructing integrated circuits

Complementary metal–oxide–semiconductor, also known as complementary-symmetry metal–oxide–semiconductor (COS-MOS), is a type of metal–oxide–semiconductor field-effect transistor (MOSFET) fabrication process that uses complementary and symmetrical pairs of p-type and n-type MOSFETs for logic functions. CMOS technology is used for constructing integrated circuit (IC) chips, including microprocessors, microcontrollers, memory chips, and other digital logic circuits. CMOS technology is also used for analog circuits such as image sensors, data converters, RF circuits, and highly integrated transceivers for many types of communication.

Programmable logic device Reprogrammable computer hardware technology

A programmable logic device (PLD) is an electronic component used to build reconfigurable digital circuits. Unlike integrated circuits (IC) which consist of logic gates and have a fixed function, a PLD has an undefined function at the time of manufacture. Before the PLD can be used in a circuit it must be programmed (reconfigured) by using a specialized program.

Application-specific integrated circuit Integrated circuit customized (typically optimized) for a specific task

An application-specific integrated circuit is an integrated circuit (IC) chip customized for a particular use, rather than intended for general-purpose use. For example, a chip designed to run in a digital voice recorder or a high-efficiency bitcoin miner is an ASIC. Application-specific standard product (ASSP) chips are intermediate between ASICs and industry standard integrated circuits like the 7400 series or the 4000 series. ASIC chips are typically fabricated using metal-oxide-semiconductor (MOS) technology, as MOS integrated circuit chips.

In digital electronics, the fan-out is the number of gate inputs driven by the output of another single logic gate.

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Gate array

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In digital circuit design, register-transfer level (RTL) is a design abstraction which models a synchronous digital circuit in terms of the flow of digital signals (data) between hardware registers, and the logical operations performed on those signals.

In computer engineering, a logic family is one of two related concepts:

The OR gate is a digital logic gate that implements logical disjunction (∨) from mathematical logic – it behaves according to the truth table above. A HIGH output (1) results if one or both the inputs to the gate are HIGH (1). If neither input is high, a LOW output (0) results. In another sense, the function of OR effectively finds the maximum between two binary digits, just as the complementary AND function finds the minimum.

Standard cell

In semiconductor design, standard cell methodology is a method of designing application-specific integrated circuits (ASICs) with mostly digital-logic features. Standard cell methodology is an example of design abstraction, whereby a low-level very-large-scale integration (VLSI) layout is encapsulated into an abstract logic representation. Cell-based methodology — the general class to which standard cells belong — makes it possible for one designer to focus on the high-level aspect of digital design, while another designer focuses on the implementation (physical) aspect. Along with semiconductor manufacturing advances, standard cell methodology has helped designers scale ASICs from comparatively simple single-function ICs, to complex multi-million gate system-on-a-chip (SoC) devices.

NAND gate

In digital electronics, a NAND gate (NOT-AND) is a logic gate which produces an output which is false only if all its inputs are true; thus its output is complement to that of an AND gate. A LOW (0) output results only if all the inputs to the gate are HIGH (1); if any input is LOW (0), a HIGH (1) output results. A NAND gate is made using transistors and junction diodes. By De Morgan's laws, a two-input NAND gate's logic may be expressed as AB=A+B, making a NAND gate equivalent to inverters followed by an OR gate.

The NOR gate is a digital logic gate that implements logical NOR - it behaves according to the truth table to the right. A HIGH output (1) results if both the inputs to the gate are LOW (0); if one or both input is HIGH (1), a LOW output (0) results. NOR is the result of the negation of the OR operator. It can also in some senses be seen as the inverse of an AND gate. NOR is a functionally complete operation—NOR gates can be combined to generate any other logical function. It shares this property with the NAND gate. By contrast, the OR operator is monotonic as it can only change LOW to HIGH but not vice versa.

NanGate, Inc was a privately held US/Silicon Valley-based multinational corporation dealing in Electronic Design Automation (EDA) for electrical engineering and electronics until its acquisition by Silvaco, Inc. in 2018. NanGate was founded in October 2004 by a group of semiconductor professionals with a background from Intel Corporation and Vitesse Semiconductor Corp. The company has received capital investments from a group of Danish business angels and venture capital companies. The company is today owned and controlled by its management following a management buy-out in 2012. NanGate markets a range of software products and design services for the design and optimization of standard cell libraries and application-specific integrated circuits. The market focus is standard cell library design and optimization for 14-28 nanometer CMOS processes.

Memory cell (computing) Part of computer memory

The memory cell is the fundamental building block of computer memory. The memory cell is an electronic circuit that stores one bit of binary information and it must be set to store a logic 1 and reset to store a logic 0. Its value is maintained/stored until it is changed by the set/reset process. The value in the memory cell can be accessed by reading it.

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