What is transistor-to-transistor logic (TTL)? - Definition from WhatIs.com

Definition

transistor-to-transistor logic (TTL)

Part of the Microprocessors glossary:

Transistor-transistor logic (TTL) is a digital logic design in which bipolar transistor s act on direct-current pulses. Many TTL logic gate s are typically fabricated onto a single integrated circuit (IC). TTL ICs usually have four-digit numbers beginning with 74 or 54.

A TTL device employs transistor s with multiple emitters in gates having more than one input. TTL is characterized by high switching speed (in some cases upwards of 125 MHz ), and relative immunity to noise . Its principle drawback is the fact that circuits using TTL draw more current than equivalent circuits using metal oxide semiconductor ( MOS ) logic. Low-current TTL devices are available, but the reduced current demand comes at the expense of some operating speed.

This was last updated in March 2011
Posted by: Margaret Rouse

Related Terms

Definitions

  • cache memory

    - Cache memory, also called CPU memory, is random access memory (RAM) that a computer microprocessor can access more quickly than it can access regular RAM. (SearchStorage.com)

  • BIOS (basic input/output system)

    - BIOS (basic input/output system) is the program a personal computer's microprocessor uses to get the computer system started after you turn it on. It also manages data flow between the computer's o... (WhatIs.com)

  • quad-core processor

    - A quad-core processor is a chip with four independent units called cores that read and execute central processing unit (CPU) instructions such as add, move data, and branch. (WhatIs.com)

Glossaries

  • Microprocessors

    - Terms related to microprocessors, including definitions about silicon chips and words and phrases about computer processors.

  • Internet applications

    - This WhatIs.com glossary contains terms related to Internet applications, including definitions about Software as a Service (SaaS) delivery models and words and phrases about web sites, e-commerce ...

Ask a Question About transistor-to-transistor logic (TTL)Powered by ITKnowledgeExchange.com

Get answers from your peers on your most technical challenges

Tech TalkComment

Share
Comments

    Results

    Contribute to the conversation

    All fields are required. Comments will appear at the bottom of the article.