数字电子技术(课件)lec.ppt
2023/11/14,Chapter 10 Memory and Storage,1,Lecture 24 Outline,10-5Flash Memories10-6Memory Expansion10-7Special Types of Memories*Memory Application,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,2,Key Knowledge in Lecture 24,Operation principle of flash memory.Memory word-length expansion and word capacity expansion connection.Determine the address range for each memory chip.FIFO memories and their application.LIFO memories and their use as stack,Difficult Topics:Memory expansion method;Determine the address range of memory chip.,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,3,The Storage Cell in a Flash Memory,Flash memories are high-density read/write nonvolatile memories.The storage cell consists of a single floating gate MOS transistor.,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,4,Simplified Illustration of Storing a 0 or a 1,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,5,The Read Operation of a Flash Cell in An Array,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,6,Simplified Illustration of Removing Charge from a Cell,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,7,Basic Flash Memory Array,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,8,Two Types of Memory Expansion,Lecture 24:Memory Expansion,Application,Word-length expansion:expand the number of bits in each address.,2023/11/14,Chapter 10 Memory and Storage,9,Memory Expansion Example 1,Lecture 24:Memory Expansion,Application,Expand the 64k x 4 ROM to form a 64k x 8 ROM.,2023/11/14,Chapter 10 Memory and Storage,10,Memory Expansion Example 1 Solution,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,11,Memory Expansion Example 2 and the Solution,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,12,RAM Word-Length Expansion Illustration,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,13,RAM Word-Length Expansion Example,Lecture 24:Memory Expansion,Application,Use 1M x 4 SRAM to create a 1M x 8 SRAM.,2023/11/14,Chapter 10 Memory and Storage,14,Two Types of Memory Expansion,Lecture 24:Memory Expansion,Application,2.Word-capacity expansion:expand the number of different addresses.,2023/11/14,Chapter 10 Memory and Storage,15,Word-Capacity Expansion Example 1,Use 512k x 4 RAMs to implement a 1M x 4 memory.,Lecture 24:Memory Expansion,Application,How to expand memory with more than two chips?,2023/11/14,Chapter 10 Memory and Storage,16,Word-Capacity Expansion Example 2,Lecture 24:Memory Expansion,Application,Use 8k x 8 RAMs to implement a 32k x 8 memory.,2023/11/14,Chapter 10 Memory and Storage,17,Determine the Address Range of Each Memory Chip,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,18,Memory Modules,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,19,Inserting a SIMM/DIMM into a Socket,Lecture 24:Memory Expansion,Application,SIMM has 32-bit data path,DIMM has 64-bit data path.,2023/11/14,Chapter 10 Memory and Storage,20,Special Types of Memories,Lecture 24:Memory Expansion,Application,First in-First out(FIFO)Memories,2023/11/14,Chapter 10 Memory and Storage,21,Block Diagram of a Typical FIFO Serial Memory,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,22,FIFO Register in Data-Rate Buffering Applications,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,23,Last In-First Out(LIFO)Memories,Lecture 24:Memory Expansion,Application,Register stack(堆栈),2023/11/14,Chapter 10 Memory and Storage,24,Simplified Illustration of Pushing Data onto the Stack,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,25,Simplified Illustration of Pulling Data from the Stack,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,26,RAM stack,Lecture 24:Memory Expansion,Application,Representation of a 64kB memory with the 16-Bit Addresses Expressed in Hexadecimal,2023/11/14,Chapter 10 Memory and Storage,27,Illustration of PUSH Operation for a RAM Stack,Lecture 24:Memory Expansion,Application,For a register stack,the data moves up or down from one location to the next.In a RAM stack,the data itself does not move but the top-of-stack moves under control of a register called the stack pointer(堆栈指针).,2023/11/14,Chapter 10 Memory and Storage,28,Illustration of POP Operation for the RAM Stack,Lecture 24:Memory Expansion,Application,The last data word stored in the stack is read first.Then the stack pointer is incremented by two.,Keep in mind that RAMs are nondestructive,so the data word still remains in the memory after a pop operation.,2023/11/14,Chapter 10 Memory and Storage,29,CCD(charge-coupled device)Memories,Lecture 24:Memory Expansion,Application,A CCD channel,The CCD memory stores data as charges on capacitors.Unlike the DRAM,however,the storage cell does not include a transistor.,The CCD memory consists of long rows of semiconductor capacitors,called channels.,Data are entered into a channel serially by depositing a small charge for 0 and large charge for 1 on the capacitors.,2023/11/14,Chapter 10 Memory and Storage,30,Block Diagram of the Complete Security System,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,31,Block Diagram of the Memory Logic,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,32,Memory Cell Logic,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,33,The Memory Address Decoder,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,34,Memory Array and Address Decoder,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,35,Illustration of Entering a Security Code(4739),Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,36,The Complete Memory Logic,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,37,The Security Code Logic(From Chapter 9),Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,38,The Complete Security System,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,39,Summary of Lecture 24,Flash memory cell uses charge or no charge to store data bit 0 or 1.Word-length expansion expand the number of bits in each address.Word-capacity expansion expand the number of different addresses.The address range of memory chip is determined by looking at the base address and/CS address.FIFO register is used in data-rate buffering application.LIFO register is mainly used as a stack.CCD device uses charges in a capacitor to store data 1.The charge is shifted serially.Access time is large.A 4x4 security system memory design is illustrated.,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,40,Thank you for your participation!,The End of Lecture 24,Lecture 24:Memory Expansion,Application,2023/11/14,Chapter 10 Memory and Storage,41,Two way interactive question-and-answer session.,Homework assignment:P418P419,17,21,22,Class evaluation and problem assignment,Lecture 24:Memory Expansion,Application,
