A high speed 16 kbit ECL RAM
A 16384 /spl times/ 1 bit ECL RAM (emitter coupled logic random access memory) with an access time of 15 ns and a power dissipation of 700 mW has been developed. The high packing density and performance were achieved by using a p-n-p load cell, a novel ECL circuit, and U-groove isolation. The test results proved that a p-n-p load cell is very effective in producing a fast high-density bipolar RAM having a capacity of over 64 Kbits.
A 2-ns 16K bipolar ECL RAM with reduced word-line voltage swing
A reduced word-line voltage swing (RWS) circuit configuration that results in a high-speed bipolar ECL (emitter coupled logic) RAM is proposed. The write operation can be performed with the configuration in the condition of reduced word-line voltage swing, which causes write operation error in conventional circuit configurations. The proposed configuration cuts off the hold current of the selected memory cell, and then the low-voltage node is charged up through the load p-n-p transistor. A 16-kb ECL RAM with a p-n-p loaded memory cell was fabricated by advanced silicide-base transistor (ASBT) process technology. A 2-ns access time was obtained with 1.8-W power consumption in which the word-line voltage swing was reduced by 0.7 V from a conventional case. Simulation results show that the access time is improved by 25% compared with a conventional case. Simulation results also show that writing time becomes comparable with the conventional time of 1.7 ns when the load p-n-p transistor has a saturation current of 5.0* 10/sup 17/ A and a current gain of 1.0. The saturation current is 5 times larger and the current gain is 5 times smaller than those of the standard lateral p-n-p transistor. >
Microwave source with enhanced radiation power based on orbitron MASERs
We have proposed the design of high power microwave source in a vacuum tube based on the theory of negative mass instability. The proposed source does not operate based on a slow-wave structure but instead makes use of accelerated charged particles. In our structure, an electron emitter injects the charged particles into to the cavity. Emitted particles move around the anode, which leads to electron acceleration and emission of electromagnetic waves with a specific frequency. In this paper, we have enhanced the output power and frequency of microwave source by variation of particles initial energy and the number of anodes incorporating their specific arrangement and applied voltages. Working at room temperature, compactness, wide bandwidth, and tunability of output frequency are among the advantages of the proposed source.