Network interface cards
NETWORK Interfacing cards is also known as network adopter. the purpose of this card is to connect third party devices with computer system. it having own device driver
to install for working this card.
Repeaters
Repeaters or hubs work at the OSI physical layer to regenerate the network’s signal and resend them to other segments
Primitive hub can be viewed as a multi port repeater
It regenerates data and broadcasts them to all ports
Hubs
Intelligent hubs have console ports, to allow monitoring of the hubs status and port activity.
Passive hubs just repeat any incoming signals to every port available, therefore does not act as a line repeater.
Passive hubs just split signals to multiple ports but do not regenerate the signals, which means that they do not extend a cable’s length. They only allow two or more hosts to connect to the same cable segment.
Active hubs regenerate signals.
Hubs utilize star topology.
Bridges
Has one input and one output
Used to isolate network traffic and computers
Has the intelligent to examine incoming packet source and destination addresses
But cannot interpret higher-level information
Hence cannot filter packet according to its protocol
Routers
Routers are OSI network layer 3 devices
Using interface modules can connect different layer 2 technologies e.g. Ethernet, FDDI, token ring etc…
Routers have the capability to interconnect network segments or entire networks (WANS/MANS).
These devices examine incoming packets to determine the destination address of the data. It then examines its internal routing table to choose the best path for the packet through the network, and switches them to the proper outgoing port.
Switches
fayyaz
A switch is a mufti-port bridge.
It operates at OSI data link layer 2.
It stores MAC addresses in an internal lockup table.
Temporary switched paths are created between the frame’s source destination.
Some Switches have limited layer 3 IP routing capabilities.
Switches can be configured to use V LANS.
Switches support spanning tree protocol to create resilient networks.
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LM317 (LM317)
3-Terminal Adjustable Regulator
GENERAL DESCRIPTION
The LM317 series of adjustable 3-terminal positive voltage regulators is capable of supplying in excess of 1.5A over a 1.2V to 37V output range. They are exceptionally easy to use and require only two external resistors to set the output voltage. Further, both line and load regulations are better than standard fixed regulators. Also, the LM317 is packaged in standard transistor packages which are easily mounted and handled.
In addition to higher performance than fixed regulators, the LM317 series offers full overload protection available only in IC’s. Included on the chip are current limit, thermal overload protection and safe area protection. All overload protection circuitry remains fully functional even if the adjustment terminal is disconnected.
Normally, no capacitors are needed unless the device is situated more than 6 inches from the input filter capacitors in which case an input bypass is needed. An optional output capacitor can be added to improve transient response. The adjustment terminal can be bypassed to achieve very high ripple rejection ratios which are difficult to achieve with standard 3-terminal regulators. Besides replacing fixed regulators, the LM317 is useful in a wide variety of other applications. Since the regulator is “floating” and sees only the input-to-output differential voltage, supplies of several hundred volts can be regulated as long as the maximum input to output differential is not exceeded, i.e. avoid short-circuiting the output.
Also, it makes an especially simple adjustable switching regulator, a programmable output regulator, or by connecting a fixed resistor between the adjustment pin and output, the LM317 can be used as a precision current regulator. Supplies with electronic shutdown can be achieved by clamping the adjustment terminal to ground which programs the output to 1.2V where most loads draw little current.
GENERAL DESCRIPTION
The LM317 series of adjustable 3-terminal positive voltage regulators is capable of supplying in excess of 1.5A over a 1.2V to 37V output range. They are exceptionally easy to use and require only two external resistors to set the output voltage. Further, both line and load regulations are better than standard fixed regulators. Also, the LM317 is packaged in standard transistor packages which are easily mounted and handled.
In addition to higher performance than fixed regulators, the LM317 series offers full overload protection available only in IC’s. Included on the chip are current limit, thermal overload protection and safe area protection. All overload protection circuitry remains fully functional even if the adjustment terminal is disconnected.
Normally, no capacitors are needed unless the device is situated more than 6 inches from the input filter capacitors in which case an input bypass is needed. An optional output capacitor can be added to improve transient response. The adjustment terminal can be bypassed to achieve very high ripple rejection ratios which are difficult to achieve with standard 3-terminal regulators. Besides replacing fixed regulators, the LM317 is useful in a wide variety of other applications. Since the regulator is “floating” and sees only the input-to-output differential voltage, supplies of several hundred volts can be regulated as long as the maximum input to output differential is not exceeded, i.e. avoid short-circuiting the output.
Also, it makes an especially simple adjustable switching regulator, a programmable output regulator, or by connecting a fixed resistor between the adjustment pin and output, the LM317 can be used as a precision current regulator. Supplies with electronic shutdown can be achieved by clamping the adjustment terminal to ground which programs the output to 1.2V where most loads draw little current.
LM35DZ
Precision Centigrade Temperature Sensors
GENERAL DESCRIPTION
The LM35 series are precision integrated-circuit temperature sensors, whose output voltage is linearly proportional to the Celsius (Centigrade) temperature. The LM35 thus has an advantage over linear temperature sensors calibrated in Kelvin, as the user is not required to subtract a large constant voltage from its output to obtain convenient Centigrade scaling. The LM35 does not require any external calibration or trimming to provide typical accuracies of ±1⁄4°C at room temperature and ±3⁄4°C over a full −55 to +150°C temperature range. Low cost is assured by trimming and calibration at the wafer level. The LM35’s low output impedance, linear output, and precise inherent calibration make interfacing to readout or control circuitry especially easy. It can be used with single power supplies, or with plus and minus supplies. As it draws only 60 μA from its supply, it has very low self-heating, less than 0.1°C in still air. The LM35 is rated to operate over a −55° to +150°C temperature range, while the LM35C is rated for a −40° to +110°C range (−10° with improved accuracy). The LM35 series is available packaged in hermetic TO-46 transistor packages, while the LM35C, LM35CA, and LM35D are also available in the plastic TO-92 transistor package. The LM35D is also available in an 8-lead surface mount small outline package and a plastic TO-220 package.
GENERAL DESCRIPTION
The LM35 series are precision integrated-circuit temperature sensors, whose output voltage is linearly proportional to the Celsius (Centigrade) temperature. The LM35 thus has an advantage over linear temperature sensors calibrated in Kelvin, as the user is not required to subtract a large constant voltage from its output to obtain convenient Centigrade scaling. The LM35 does not require any external calibration or trimming to provide typical accuracies of ±1⁄4°C at room temperature and ±3⁄4°C over a full −55 to +150°C temperature range. Low cost is assured by trimming and calibration at the wafer level. The LM35’s low output impedance, linear output, and precise inherent calibration make interfacing to readout or control circuitry especially easy. It can be used with single power supplies, or with plus and minus supplies. As it draws only 60 μA from its supply, it has very low self-heating, less than 0.1°C in still air. The LM35 is rated to operate over a −55° to +150°C temperature range, while the LM35C is rated for a −40° to +110°C range (−10° with improved accuracy). The LM35 series is available packaged in hermetic TO-46 transistor packages, while the LM35C, LM35CA, and LM35D are also available in the plastic TO-92 transistor package. The LM35D is also available in an 8-lead surface mount small outline package and a plastic TO-220 package.
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