With the advent of medium-scale and large-scale integrated circuits, all-electronic solid-state memories have become a reality. Semiconductor memories are smaller than equivalent core memories; they can be faster and consume less power; and in the long run, semiconductor memories will probably be substantially cheaper.

Bipolar-transistor static memorics, which are essentially multiple flip-flop registers plus read/write/selection circuits, are directly compatible with transistor/transistors or emitter-coupled logic and are very fast: read and write times below 50 nsec are readily possible. No rewriting after reading is needed (nondestructive readout, NDRO). Bipolar memories are fairly complex integrated circuits and are still expensive. They are, therefore, used mostly in small "scratchpad" memories.

隨著中規(guī)模和大規(guī)模集成電路的出現(xiàn)，全電子固態(tài)存儲器已成為現(xiàn)實。半導體存儲器比等效的磁芯存儲器體積小，速度更快，消耗的功率更少，而且，其價格最終大概會便宜得多。

雙極晶體管靜態(tài)存儲器本質上是由多觸發(fā)寄存器加上讀、寫、選擇電路構成的存儲器，直接與晶體管/晶體管邏輯電路或射極耦合電路兼容，速度又非常快：讀、寫時間很容易達到50毫微秒以下。讀出后無需重寫（非破壞性讀出，NDRO)。雙極存儲器是相當復雜的集成電路，現(xiàn)在的價格仍然很貴。因此，它們主要用于小型的“哲時"存儲器。

MOSFET (metal-oxide-silicon field-effect transistor) semiconductor memories involve simpler integrated-circuit patterns and are cheaper than bipolar memories. While older MOSFET circuits needed level-changing amplifiers to supply large logic-voltage swings, some newer MOSFET memories are TTL-compatible. MOSFET memories also come as static (flip-flop-register) memories but usually as dynamic memories. In a dynamic memory, each bit is stored in a shift register whose output is fed back to the input through a clock-gated MOSFET refresh amplifier, so each stored bit is recirculated and regenerated, say, 1000 times/sec. The refresh amplifier can be time-shared among 16 to 32 memory cells. Simple silicon-substrate MOSFET memories are slower than bipolar memories (and slower than some core memories). Typical access times are between 300u sec and 2u sec with nondestructive readout. Different types of MOSFET circuits (complementary MOSFETs, sapphire and garnet substrates) are under active development and can be expected to lead to substantially faster MOSFET memories. Compared to core memories, semiconductor memories have the advantage of nondestructive read-out. On the other hand, semiconductor memories are volatile; i.e., memory contents are destroyed when computer power is turned off. In sufficiently critical applications, one must provide an emergency power source, such as a trickle-charged battery which, when a power failure is sensed, can take over memory operation for a time sufficient to transfer the entire contents of the memory onto an auxiliary magnetic storage medium (disk or tape).

MOSFET（金屬氧化物硅場效應晶體管）半導體存儲器的集成電路結構比較簡單，價格比雙極存儲器便宜。雖然老式MOSFET電路曾需要變電平放大器來供給大的邏輯電壓變動，但是一些新的MOSFET存儲器卻是與晶體管-晶體管邏輯電路兼容的。MOSFET存儲器也可作為靜態(tài)（觸發(fā)寄存器）存儲器，但通常是作為動態(tài)存儲器的。在動態(tài)存儲器中，每一個位都存儲在移位寄存器中，移位寄存器的輸出再通過具有時鐘脈沖門的MOSFET更新放大器被反饋給輸入。因此，每一個存儲起來的位都以，譬如說每秒一千次的速度反復循環(huán)和反復產(chǎn)生。更新放大器能在16~32個存儲單元中間進行分時。簡單的硅襯底MOSFET存儲器比雙極存儲器速度慢（也比某些磁芯存儲器的速度慢）。典型的存取時間在300微秒到2微秒之間，而且讀出是非破壞性的。不同類型的MOSFET電路（互補型MOSFET，藍寶石和石榴石襯底），都在積極研制之中，并可望發(fā)展成速度快得多的MOSFET存儲器。同磁芯存儲器相比，半導體存儲器具有非破壞性讀出的優(yōu)點。另一方面，半導體存儲器是易失的，即如果計算機的電源被切斷的話，存儲器里的信息就會被破壞掉。因此，在特別重要的應用場合，必須配備緊急電源，例如連續(xù)充電池，一旦檢測到電源故障，該電池即可接替存儲操作，使存儲器的全部信息有足夠時間轉移到輔助磁性存儲媒體（磁盤或磁帶）上去。

Plated-wire memories are magnetic memories which utilize small zones of magnetizable thin films plated onto wires, rather than magnetic cores, for bit storage. Plated-wire memories permit fast access (access times as low as a few hundred nanoseconds) with nondestructive readout, and are nonvolatile. But, although batch-production methods have been developed, quality control is not simple. As a result, plated-wire memories are not cheap and have been applied mostly in higher-priced digital computers (especially in aerospace-vehicle computers); MOSFET memories seem to have overtaken plated-wire circuits in the low-cost minicomputer field. This situation may or may not be changed by future improvements in plated-wire-memory fabrication.

鍍線存儲器是用鍍在線上的小區(qū)段磁化蔣膜而不用磁芯來進行位存儲的磁性存儲器。鍍線存儲器可實現(xiàn)快速存?。ù嫒r間才幾百毫微秒），其讀出又是非破壞性的，而且是非易失的。但是，雖然已經(jīng)研究出了成批生產(chǎn)的方法，質量卻不易控制。因此，鍍線存儲器的價格并不便宜，只用于高價的數(shù)字計算機（特別是用于宇航飛行器的計算機）；而MOSFET存儲器在成本低的小型計算機領域內，似乎已經(jīng)趕上了鍍線電路。將來在鍍線存儲器制作技術上的改進，也許會改變這種情況，但也許不會。

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