Designs With RAMs

An initialization test protocol is used to configure the ASIC for the test mode by providing certain initialization vectors. Note that an initialization test protocol can only be used when the RAM model is not a black box in Synopsys. Toggling the inputs of a black box will not result in any improvements in fault coverage. If the RAM model in the Synopsys library has setup/hold timing arcs between the data/address pins and the write/iead enable and RAM select pins, one must place a testjsolate attribute on it. Without a seMestJsolate on the RAM, check test will try to trace back the write/read enable and RAM select pins to infer a clock which may cause other DRC violations. 

The set test assume command can be used to get an estimate of fault coverage. This allows the user to perform analysis of the improvements in fault coverage by initializing the RAM to different states. TC does not verify these values and the user must ensure that the RAM is initialized to that state. In addition, for each of the above approaches, a test dont fault attribute should be placed on the RAM cell. This prevents the inclusion of faults associated with the RAM cell in the fault coverage calculation. 

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RAM Here RAM stands for reliability, availability and maintainability. These three factors collectively referred to as RAM are major attributes towards system design with great impact on sustainment, life cycle costs as well as system s ability to perform the intended mission and affect overall mission success. 

Fig. 27, 2,000-ton vertical lead cable press in two-column design, with hydraulic cylinder arranged in the top, with plunger piston, moving extrusion ram and stationary container... 

Fig. 44. Shop photo of 2,000-ton vertical lead sheathing press as used for the vulcanization of cables. Press in four-column design with underlying hydraulic cylinder, moving container, traversable extrusion ram and swinging device for charging of billets (By Breda Fucine, Milan)...

Fig. 47. 4,500-ton vertical twin-ram aluminum cable press in two-column design with hydraulic coupling to ensure positive ram motion... 

Fig. 89. Combined tube and rod extrusion press in three-column design with laterally arranged drive of the piercer and separate pullback devices for main ram and piercer mandrel...

Recent research efforts have resulted in the development of an interface circuit that will dependably monitor voltage availability and switch between external power and battery back-up as needed. The circuit and the lithium battery have been incorporated into module form. One module design even contains a 16K RAM. Modules are designed to be mounted on a printed circuit board, thus providing system designers with a black-box method of meeting the need for non-volatile memory. 

When the bulk containing the binder is uniform, it is compressed on pneumatic, hydraulic, or ram-type presses. Compression can be carried out in presses provided with suitably designed cavities or in metallic pans. The pans ate filled with the powder mass, and a plunger with a cross-sectional shape similar to that of the pan is used to compress the tablet. The resulting tablets ate commonly used with powder puffs or cosmetic bmshes. 

There are two types of cold feed extruders, the standard screw design type (Fig. 15) and one with a screw feed using a ram action to feed the extruder. In both... 

A spherical preventer contains a packing element that seals the space around a drillpipe. This preventer is not designed to shut off the well when the drillpipe is out of the hole, although it allows stripping operations and some pipe rotation. Hydril Corporation, Shaffer and other manufacturers provide several models with different packing system designs for specific types of service. The ram-type preventer seals the annulus around the drillpipe however, each size of ram is designated for only one size of drillpipe. In other words, the preventer with 5-in. pipe rams can provide a seal only on 5-in. drillpipe. The preventer with blind rams is used to shut in the well if the pipe is not in the hole. If this type of preventer is activated with the pipe in the hole, the pipe can be cut. 

There are also specially designed preventers with shear-blind rams. This type of ram will certainly cut the pipe and seal the open hole. Special precautions should be taken to ensure that the blind rams cannot be mistakenly closed. 

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