Static RAM - Revision history

Jnc: prepare for move

2022-09-20T00:06:56Z

prepare for move

Jnc: clarify

2022-08-09T14:54:47Z

clarify

Jnc: Reasonably complete

2022-08-02T20:20:44Z

Reasonably complete

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'''Static RAM''' ('static random-access memory') is a simple, high-performance [[memory]] technology. Unlike [[dynamic RAM]] (DRAM), it does not need to be [[refresh]]ed, making it simpler to use (at the [[hardware]] level). The lack of refresh also means that it has a constant [[access time]] - there is never a need to wait for a refresh cycle to complete.

It consists of an array of [[latch]]es, one per bit. The usual [[analog]] [[circuit]] contains two [[transistor]]s and two [[resistor]]s per bit; it thus requires more transistors per bit than DRAM. It is also volatile, like DRAM, and loses its contents if power is cut off.

It is now used for a variety of purposes in computers, including [[Central Processing Unit|CPU]] [[cache]]s, writeable [[microcode]], [[disk]] [[buffer]]s, [[bit-mapped display]]s, etc - anyplace where speed and a guaranteed fixed access time are critical. In the early days of [[personal computer]]s, it was sometimes used for [[main memory]], but not any more, since it is more expensive per bit than DRAM.

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[[Category: Memory Basics]]

← Older revision		Revision as of 00:06, 20 September 2022
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−	'''Static RAM''' ('static random-access memory') is a simple, high-performance [[memory]] technology. Unlike [[dynamic RAM]] (DRAM), it does not need to be [[refresh]]ed, making it simpler to use (at the [[hardware]] level). The lack of refresh also means that it has a constant [[access time]] - there is never a need to wait for a refresh cycle to complete.	+	'''Static RAM''' ('static random-access memory') is a simple, high-performance [[memory]] technology. Unlike [[dynamic RAM]] (DRAM), it does not need to be [[memory refresh\|refreshed]], making it simpler to use (at the [[hardware]] level). The lack of refresh also means that it has a constant [[access time]] - there is never a need to wait for a refresh cycle to complete.

	It consists of an array of [[latch]]es, one per bit. The usual [[analog]] [[circuit]] for those latches contains two [[transistor]]s and two [[resistor]]s per bit; it thus requires more transistors per bit than DRAM. It is also volatile, like DRAM, and loses its contents if power is cut off.		It consists of an array of [[latch]]es, one per bit. The usual [[analog]] [[circuit]] for those latches contains two [[transistor]]s and two [[resistor]]s per bit; it thus requires more transistors per bit than DRAM. It is also volatile, like DRAM, and loses its contents if power is cut off.

@@ Line 1: / Line 1: @@
 '''Static RAM''' ('static random-access memory') is a simple, high-performance [[memory]] technology. Unlike [[dynamic RAM]] (DRAM), it does not need to be [[refresh]]ed, making it simpler to use (at the [[hardware]] level). The lack of refresh also means that it has a constant [[access time]] - there is never a need to wait for a refresh cycle to complete.
-It consists of an array of [[latch]]es, one per bit. The usual [[analog]] [[circuit]] contains two [[transistor]]s and two [[resistor]]s per bit; it thus requires more transistors per bit than DRAM. It is also volatile, like DRAM, and loses its contents if power is cut off.
+It consists of an array of [[latch]]es, one per bit. The usual [[analog]] [[circuit]] for those latches contains two [[transistor]]s and two [[resistor]]s per bit; it thus requires more transistors per bit than DRAM. It is also volatile, like DRAM, and loses its contents if power is cut off.
 It is now used for a variety of purposes in computers, including [[Central Processing Unit|CPU]] [[cache]]s, writeable [[microcode]], [[disk]] [[buffer]]s, [[bit-mapped display]]s, etc - anyplace where speed and a guaranteed fixed access time are critical. In the early days of [[personal computer]]s, it was sometimes used for [[main memory]], but not any more, since it is more expensive per bit than DRAM.