Electronic circuit

There is an electronic circuit called a flip-flop. It consists of two transistors connected in such a way that, if a voltage is applied, one side of the circuit becomes active and the other side not if a second voltage is applied, the circuit flips so that the active side becomes inactive and vice versa. Thus, just as with a conventional switch for which one touch puts it on and a second touch turns it off, one touch of the flip-flop turns it on and a second touch turns it ojf. Addition of two binary numbers now becomes possible. Suppose we want to add 2 -(- 1 (= 3 decimal). First, the numbers must be converted into binary code (10 and 01) and these become switch settings in the machine, but we need four switches so that 10 becomes on, off and 01 becomes off, on (Figure 42.6). 

Parylene C was included among the eadiest MIL-I-46058 (51) qualified coatings (as type XY) and has since enjoyed a reputation for superior performance in protecting and preserving the operation of electronic circuits against the detrimental effects of their operating environments. 

Applications. The applications sought for these polymers include composites, stmctural plastics, electronics/circuit boards, aircraft/spacecraft coatings, seals, dental and medical prosthetics, and laser window adhesives. However, other than the early commercialization by Du Pont of the NR-150 B material, Httie development has occurred. These polymers are quite expensive ( 110 to 2200 per kg for monomers alone). 

Direct photography of drops in done with the use of fiber optic probes using either direct or reflected light. StiU or video pictures can be obtained for detailed analysis. The light transmittance method uses three components a light source to provide a uniform collimated beam, a sensitive light detector, and an electronic circuit to measure the amplified output of the detector. The ratio of incident light intensity to transmitted intensity is related to interfacial area per unit volume. 

A cable or flex circuit is often employed as an interconnection between electronic circuits that are not easily coimected by other means. The interconnection density obtained with a cable or flex circuit is lower than that achieved with a backpanel. 

MetalFoilforPrinted WiringApplications, IPC-MF-150, Institute for Interconnecting and Packaging Electronic Circuits, Liucolnwood, IU., 1991. 

Diallyl terephthalate [1026-92-2] is utilized less, but lenses made of copolymers with triaHyl cyanurate and methacrylates have been suggested (62). Diallyl tetrabromophthalate and tetrachlorophthalate polymers have been proposed for electronic circuit boards of low flammabiUty (63). They are uv-curable and solder-resistant. Copolymers with unsaturated polyester, vinyl acetate and DAP have been studied (64). 

The Weissenbetg Rheogoniometer is well suited to research on homogeneous viscoelastic fluids and elastic melts. For oscillatory shear a second motor-drive mechanism is added. This allows the use of 60 frequencies in the range of 7.6 x 10 to 40 Hz at ampHtudes between 2 x 10 and 3 X 10 rad. An electronic circuit improves the precision of oscillatory measurements, particularly at frequencies neat the natural resonance frequency of the instmment itself (298). 

The pursuit of further miniaturization of electronic circuits has made submicrometer resolution Hthography a cmcial element in future computer engineering. LB films have long been considered potential candidates for resist appHcations, because conventional spin-coated photoresist materials have large pinhole densities and variations of thickness. In contrast, LB films are two-dimensional, layered, crystalline soHds that provide high control of film thickness and are impermeable to plasma down to a thickness of 40 nm (46). The electron beam polymerization of CO-tricosenoic acid monolayers has been mentioned. Another monomeric amphiphile used in an attempt to develop electron-beam-resist materials is a-octadecylacryUc acid (8). 

The explosion-proof enclosure is designed such that an explosion in the interior of the enclosure containing the electronic circuits will be contained. The enclosure will not allow sufficient flame to escape to the exterior to cause an ignition. Also, a surface temperature rating is given to the device. This rating must indicate a lower surface temperature than the ignition temperature of the gas in the hazardous area. 

Note It is recommended to provide separate grounding for electronic circuits... 

Hexaphase electronic circuits generate maximum harmonic disorders. 

Electronic Circuits, Systems and Standards The Best ofEDN... 

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