A new circuit configuration for a static memory cell with an area of 880 /spl mu/m/sup 2/
A new 5-transistor memory cell in double polysilicon technology with depletion-load elements and a minimum linewidth of 3 /spl mu/m is presented. The circuit configuration, based on a Schmitt trigger, leads to static memory cells having a bit density of 1100 bit/mm/SUP 2/ and an average power consumption of 5.5 /spl mu/W/cell. With the help of computer simulations the static and dynamic behavior of the basic circuit are calculated and discussed in detail as well as the two possible operation modes of the memory cell. These results compare favorably with the experimental results obtained on a realized 2/spl times/4 memory array. The performance of the proposed memory cell is the same as that of a conventional 6-transistor cell, but the area is reduced.
Two static 4K clocked and nonclocked RAM designs
A detailed description of both a clocked and a nonclocked n-channel MOS 4K static RAM is presented. The clocked device is a three-supply (+12 V, +5 V, -5 V) RAM which uses bootstrapping circuitry for signal driving, and sustaining resistors for low memory array power dissipation and infinite chip select length. The nonclocked device is a single supply (+5 V) fully TTL compatible RAM with depletion load circuitry for speed and compactness. Emphasis is given to processing parameters and performances as well as circuit design considerations including internal signal timings and circuit schematics.
Effects of reservoir volume on performance of pulse tube cooler.
A pulse tube cooler has the advantages of long-life and low-vibration over conventional cryocoolers such as G-M and Stirling coolers because of the absence of moving parts at low temperature. On the other hand, the combination of a reservoir and orifice is indispensable to optimize the performance of pulse tube coolers. In order to make the pulse tube cooler compact for practical applications, the volume of reservoir should be minimized. This paper analyzes the effects of the reservoir volume on the thermodynamic performance of various components in a simple orifice and a double-inlet pulse tube cooler by combining a linearized model with a thermodynamic analysis. Expressions of entropy production for those components are presented. The results show that the reservoir volume has a significant influence on the entropy production in the various components when the reservoir to pulse tube volume ratio is smaller than about 5. The ratio is important to determine the minimum reservoir volume for a pulse tube cooler. Optimum settings for a double-inlet pulse tube cooler are also discussed.