digital logic ICs using bipolar transistors.

An output signal format defined as a rectangular wave capable of driving a multiple of TTL loads. It has a positive signal peak greater than +2.4 volts and a negative signal peak less than +0.5 volts. The number of loads must be specified (MIL-PRF-55310D, 3.6.20).

The abbreviation for "Transistor-Transistor Logic."

This is the maximum amount of time that a data packet can travel on a network before being discarded and assumed to be lost. Also, Transistor Transistor Logic, which is a specific method of wiring a digital circuit using bipolar transistors.

Abbreviation for transistor-transistor logic. Referring to logic circuits consisting of two or more directly interconnected transistors, to provide conditional switching capability.

(abb.) 1. Transistor Transistor Logic (abb.) 2. Time To Live Source: Lock Industry Standards and Training (LIST) Council

Transistor-transistor-logic. A logic signal whose "high" state is nominally 5 volts and at least 2 volts at less than 20mA, and whose "low" state is nominally 0 volts and less than 0.8 volts.

Transistor-Transistor Logic. A type of integrated circuit with nominal logic levels of +5 and 0 volts. These logic levels are often specified for digital data and control signals that connect codecs and other communications equipment.

Specifically: Transistor Transistor Logic. Generally: Single-ended signalling format for binary data. which uses levels of 0 and 5 volts (nominal). TTL is intended for high speed signalling between integrated circuits on the same or adjacent boards, although may be used at slow speeds over several feet.

Transistor-to-transistor logic. A form of solid state logic which uses only transistors to form the logic gates.

Transistor-Transistor Logic, a common type of digital circuit in which the output is derived from two transistors. The first semiconductors using TTL were developed by Texas Instruments in 1965. The term is commonly used to describe any system based on digital circuitry, as in TTL monitor.

Transistor-Transistor Logic; a fast, reasonable-cost type of integrated circuit used in some monitors.

One of the more common logic families in use today. Other logic families include CMOS (complementary metal oxide semiconductor) and ECL (emitter-coupled logic). Different logic families are distinguished by such electrical characteristics as logic levels, input current, speed, power consumption, and the supply voltage required.

An integrated circuit family that use bipolar junction transistors to build the logic gates.

Transistor-Transistor Logic - a type of bipolar logic.

See Transistor-Transistor Logic.

Abbreviation for transistor-transistor-logic. A popular logic circuit family that uses multiple-emitter transistors. A low signal state is defined as a signal 0.8V and below. A high signal state is defined as a signal +2.0V and above.

Transistor-to-Transistor Logic. A digital signal, usually 4-5 volts peak-to-peak with a distance limitation is 6-10 feet (1.8-3.0 meters). Signal splitting is acceptable. TTL signals are either on or off, and are characteristic of low resolution computers (CGA/EGA).

Circuits based on groups of transistors which respond to the presence of or lack of a low-voltage signal. TTL-level signals are usually 5-volt signals with little current-handling ability (1.7ma typ.) Many digital I/O lines are TTL-level, and therefore unable to switch power relays without the use of a buffered mounting panel like our CYSSR 24.

Transistor Transistor Logic. A logic signal that operates between 0 and +5 volt limits.

Integrated-circuit technology that uses bipolar transistor as the principal circuit element.

Transistor Transistor Logic, a digital circuit composed of bipolar transistors wired in a certain manner. Indicates a digital rather than an analog circuit. TTL gates using NPN transistors are positive-level NAND gates or negative-level NOR gates.

Time to Live. A header field for a packet sent over the Internet indicating how long the packet should be held.

Stands for Time to Live.

(Time to Live) - a field in the Internet Protocol (IP) that specifies how many more hops a packet can travel before being discarded or returned.

(Time To Live) A method for ensuring that undelivered IP datagrams are eventually discarded, rather than being continually forwarded across a network. Each packet is given a fixed time to live by the source machine. When a router forwards a packet, it decrements that packet's TTL value by one or (usually) more. When a packet's TTL reaches zero it is silently discarded.

Time to Live. A custom setting that can be set to 0 or to a specified percentage of the age of an HTTP object. This setting determines the expiration policy of HTTP objects held in the ISA Server cache.

Time to Live. A field in the IP header which indicates how long this packet should be allowed to survive before being discarded. It is primarily used as a hop count. See also: Internet Protocol. [Source: MALAMUD

See: Time to Live

Is Time to Live. TTL is a counter within an ICMP packet.

Time-To-Live; a limit on the length of time that a datagram can remain within an Internet. The TTL usually is specified as the maximum number of hops that a datagram can traverse before it must be discarded.

Time To Live, the number of seconds remaining on a cached record before it is purged. If a record is cached, the server providing the record will provide the time remaining on the TTL rather then the original length it was given.

Time to live. The amount of time an IP router holds a datagram before discarding it.

time to live. A technique used by best-effort delivery protocols to inhibit endlessly looping packets. The packet is discarded if the TTL counter reaches 0.

A technique used in best-effort delivery systems to avoid endlessly looping packets.

Time To Live. In general packet switching, a field that should be defined in the packet header used for switching (usually Layer 3, but possibly Layer 2), such that any unassured (or unreliable) network switching service is protected against the consequences of a route loop. Specifically in the Internet Protocol, a field processed by each IP router to prevent route loops. A "U" is a Unit of Measurement for Co-Location. 1U = 1.75" of Vertical Rack Space 2U = 3.5" of Vertical Rack Space 3U = 5.25" of Vertical Rack Space 4U = 7.00" of Vertical Rack Space

Time to Live. A timer value included in packets sent over TCP/IP-based networks that tells the recipients how long to hold or use the packet or any of its included data before expiring and discarding the packet or data. For DNS, TTL values are used in resource records within a zone to determine how long requesting clients should cache and use this information when it appears in a query response answered by a DNS server for the zone. See also: DNS Server; Domain Name System (DNS); packet; resource record (RR); Transmission Control Protocol/Internet Protocol (TCP/IP); zone

Time to live. The TTL counter specifies the maximum number of hops that an IP data packet can traverse in the network before an intermediate router discards the packet, thus preventing packets from looping endlessly through the network.

The Time To Live

Time to Live. A field in the IP header which indicates how long this packetshould be allowed to survive before being discarded. It isprimarily used as a hop count. See also: Internet Protocol.[Source: MALAMUD] TITLE (of a document)

Through The Lens. A type of scene metering in which the camera accepts information directly through the lens. (For example, a TTL light meter or TTL flash meter.)

Through The Lens. Electronic metering feature that measures the amount of ambient and electronic light through the lens. It is used mostly to control flash timing and exposure.

"through the lens", referring to a metering system where it meters through the lens which takes the photograph.

Through The Lens: A metering system in which a light meter within the camera body measures exposure from the image-forming light that has passed through the lens. (see Meter)

Abbreviation for through-the-lens, used of viewfinders that show EXACTLY what the lens sees - thus there is no parellax error between the view finder and the image recording device.

hrough he ense - Metering that allows the camera to judge exposure on information actually being recorded.

Mode Through the lens incoming flash light is measured directly on the film level and the light output is ended, as soon as the subject has been correctly lit.

A metering system in which the camera measures the actual light entering the lens.

Through-the-lens. Camera that has a viewfinder looking through the same lens.

"Through The Lens"; Exposure measurement through the lens of the camera. As a result, delayed exposure can be accounted for and controlled with a correcting filter.

This expression designates light metering systems installed inside the camera itself. Even though it applies to both ambient and artificial (flash) light, TTL is used primarily to describe an automatic, built-in flash exposure control system used in modern cameras.

Refers to a metering system that utilizes a light-sensitive mechanism within the camera body to measure exposure from image light passing through the lens. TTL viewfinders reveal exactly what the lens sees, avoiding parallax problems. See also Autofocus TTL.

Abbreviation for through the lens, as in through-the-lens viewing or metering.

Through the Lens - term used when talking about auto focus or auto exposure systems that work through the camera's lens.

Through The Lens. Metering system on many electronic camera systems which allows for the camera and a dedicated flash unit to determine proper exposure based on aperture, shutter speed and flash power. Another option is the Evaluative Through The Lens (ETTL) metering which involves use of 3D matrix Metering and a series of per-flashes to determine the proper exposure. Type of exposure meter built into the camera body and reading through the camera lens. May measure either at full aperture or at picture taking aperture. (refer below for more descriptions).

(Through The Lens) metering: A meter built into the camera body that uses light coming through the tens to set the exposure.

A camera design that let's you compose an image while looking at the scene through the lens that will take the picture. Also called thru-the-lens.