Difference between SDRAM and EDO or FPM DRAM?

Question

What is the Difference between SDRAM and EDO or FPM DRAM

Answer 1

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Answer 2

EDO RAM = Extended Data Output Random Access Memory.
A type of random access memory chip that improves the time to read from memory on faster microprocessors.
FPM DRAM + Fast Page Mode RAM.
A type of Dynamic RAM (DRAM) that allows faster access to data in the same row or page. Page-mode memory works by eliminating the need for a row address if data is located in the row previously accessed.
SDRAM = Synchronous DRAM.
A type of DRAM that can run at much higher clock speeds than conventional memory. SDRAM actually synchronizes itself with the CPU's bus and is capable of running at 133 MHz, about three times faster than conventional RAM.

Answer 3

SDRAM - short for Synchronous DRAM, a type of DRAM (Dynamic Random Access Memory, a type of memory used in most personal computers) that can run at much higher clock speeds than conventional memory. SDRAM actually synchronizes itself with the CPU's bus and is capable of running at 133 MHz, about three times faster than conventional FPM RAM, and about twice as fast EDO DRAM and BEDO DRAM. SDRAM is replacing EDO DRAM in many newer computers.

EDO RAM - Short for Extended Data Out Dynamic Random Access Memory, a type of DRAM that is faster than conventional DRAM. Unlike conventional DRAM which can only access one block of data at a time, EDO RAM can start fetching the next block of memory at the same time that it sends the previous block to the CPU.

FPM DRAM - short for Fast Page Mode RAM, a type of Dynamic RAM (DRAM) that allows faster access to data in the same row or page. Page-mode memory works by eliminating the need for a row address if data is located in the row previously accessed. It is sometimes called page mode memory.

FPM RAM is being replaced by newer types of memory, such as SDRAM.

Answer 4

SDRAM(Synchronous Dynamic random) access memory which is a type of solid state computer memory.

Other dynamic random access memories (DRAM) have an asynchronous interface which means that it reacts as quickly as possible to changes in control inputs. SDRAM has a synchronous interface, meaning that it waits for a clock signal before responding to its control inputs. It is synchronized with the computer's system bus, and thus with the processor. The clock is used to drive an internal finite state machine that pipelines incoming commands. This allows the chip to have a more complex pattern of operation than DRAM which does not have synchronizing control circuits.SDRAM chips are rated according to their maximum clock rate and their read cycle time.

EDO DRAM is similar to Fast Page Mode DRAM with the additional feature that a new access cycle can be started while keeping the data output of the previous cycle active. This allows a certain amount of overlap in operation (pipelining), allowing somewhat improved speed. It was 5% faster than Fast Page Mode DRAM.EDO's speed and capabilities allowed it to somewhat replace the then-slow L2 caches of PCs.

Dynamic random access memory (DRAM) is a type of random access memory that stores each bit of data in a separate capacitor. As real-world capacitors are not ideal and hence leak electrons, the information eventually fades unless the capacitor charge is refreshed periodically. Because of this refresh requirement, it is a dynamic memory as opposed to SRAM and other static memory. Its advantage over SRAM is its structural simplicity: only one transistor and a capacitor are required per bit, compared to six transistors in SRAM. This allows DRAM to reach very high density. Since DRAM loses its data when the power supply is removed, it is in the class of volatile memory devices.



Fast page mode DRAM is also called FPM DRAM, Page mode DRAM, Fast page mode memory, or Page mode memory.
In page mode, much as in VRAM, a row of the DRAM can be kept "open", so that successive reads or writes within the row do not suffer the delay of precharge and accessing the row. This increases the performance of the system when reading or writing bursts of data.

Answer 5

hello,In terms of RAM's (Random Access Memories), there are two basic types, SRAM's and DRAM's. RDRAM's and SDRAM's are types of DRAM's. SRAM's store bits (1's or 0's) in memory cells that are basically flip flops. In a logic diagram, an SRAM memory cell may look like two cross-connected NAND or NOR gates - that is, the output of each NAND or NOR gate is connected to one input of the other NAND or NOR gate.This is a "flip flop", which can store a 1 or a zero for as long as you apply power - but not very much power. Very little power consumption is experienced except during transitions – writing into the memory cell. Static power consumption (without transitions) is very low because the flip flop is based on CMOS NAND or NOR gates where either a P-channel or an N-channel transistor conducts, but not both – and the P and N channel transistors are connected in such a way that there is no conduction path from the power supply to ground so power is not consumed in the static state (except through leakage). The advantages of SRAM's are their very high speed and very low power consumption - but SRAM memory cells generally require 6 transistors (there are efforts towards memory cells based on fewer transistors, such as 4 transistor cells). So, the simple answer to your question is that SRAM’s, Static Random Access Memories, are the fastest. DRAM’s store bits in memory cells that are basically capacitors under transistors. The transistor is used as a relay to the capacitor, and the capacitor stores a bit (a "1" or a "0") as either storing charge on the capacitor or not storing charge. However, the charge on a capacitor gradually leaks out over time – so, periodically (generally several thousand times per second), the contents of a DRAM need to read out and then rewritten back in – this is called a "refresh cycle", or a "refresh". As you might expect, the refresh consumes a lot of power. DRAM’s consume more power, and are slower than SRAM’s – but because a DRAM cell uses just one transistor (with a capacitor) compared to 6 transistors for an SRAM cell, a DRAM memory is much cheaper than an SRAM memory.