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RANTLE Memory IC provides a complete power supply for DDR2, DDR3, and DDR3L memory systems in the lowest total cost and minimum space. It integrates a synchronous buck regulator controller with a 2-A sink and buffered low noise reference.
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RANTLE provides many parts of Memory IC such as serial EEPROM, serial EERAM, serial flash and many more. Memory IC is a high-performance CMOS, significantly improving performance and reliability while lower power consumption.
RANTLE Memory IC have standalone volatile memory that offers designers an easy and inexpensive way to add more RAM to their application. It has 8-pin devices which has unlimited endurance and zero write times.
RANTLE memory IC offers low cost, non-volatile RAM storage via an external battery and is ideal for applications that need to write very often to the memory. With fast parallel access times provide secure, unalterable memory for excellent firmware and data protection.
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RANTLE memory IC enables stored data to be updated byte-by-byte or by full sector, providing design flexibility. The parallel interface devices offer faster read times than serial interface protocol. RANTLE provides a complete selection of densities, operating voltages, and devices packages.
RANTLE Memory IC are used extensively across a broad spectrum of products including telecommunication, avionics, and military application.
The electronic components manufacturers’ engineers’ team carefully chooses material and technology for manufacturing all Memory IC.
Our Memory IC are precisely machined and tested to meet high-quality standards. For almost 16 years RANTLE became the best partner of all electronic consumers.
RANTLE offers high quality service, competitive price, fast delivery, global sourcing network, quality warranted products and excellent after-sale service. Our control team is working hard to ensure the quality of all the parts we are selling.
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Memory IC: The Ultimate FAQ Guide
If you have any question on memory IC, this guide has all the answers you need.
It covers everything about memory chips, from the basic definition to more advanced concepts.
Ideally, aims at making you an expert in the memory integrated circuits industry.
Let’s have a look:
- What is Memory IC?
- Why use Memory IC?
- Is there a difference between Memory Module and Memory IC?
- Which Type of Memory ICs are there?
- Which Technology did Memory ICs Replace?
- What do Memory ICs do?
- How do you Test Memory IC?
- What are the Characteristics of Memory IC?
- How is Memory IC Made?
- How does Memory Integrated Circuits Store Data?
- How do you Read Memory ICs?
- Can you Erase Data from Memory ICs?
- Which Format does Memory Integrated Circuit Store Data?
- How many times can you Erase Data from Memory IC?
- How will you know Memory IC is damaged?
- Which Industries use Memory ICs?
- Is there difference between Microprocessor and Memory IC?
- How best can you Package Memory IC?
- How do you Specify Memory IC?
- How can you Identify Various Types of Memory?
- What is Semi-conductor Memory?
- What are the Quality Standards for Memory Chip?
- What are the Technological Advancements in Memory Chip Industry?
- How does On-chip Memory and Off-chip Memory compare?
- What Determines Speed of Memory Chips?
- How much Data Can Memory IC hold?
- What is Memory Chip Address?
- What is the difference between Address Bus and Data Bus in Memory Chip?
- What is the Internal Organization of Memory Chips?
- What should you consider before buying Memory Chips?
What is Memory IC?
You can use memory IC as either volatile or non-volatile type.
Volatile memory is a memory type that stores data only when a device is powered. Loss of power results in the loss of data held.
Non-volatile memory is a memory type which can hold stored data even in the absence of power.
Why use Memory IC?
You find the use of Memory ICs in various applications including:
Electronic devices that are memory-based such as computers, phones and communication equipment employ Memory ICs to store their information.
Smart cards like bank cards and new generation identity cards such as driver’s license and electronic passports utilize Memory ICs.
Memory ICs are used to hold the card holder’s personal information and records.
Is there a difference between Memory Module and Memory IC?
A memory module refers to a configured circuit board on which Memory ICs are arranged.
Memory modules you can find include the single in-line memory module and the dual in-line memory modules.
Which Type of Memory ICs are there?
There are two broad types of Memory ICs that you will encounter: volatile Memory ICs and non-volatile memory ICs.
Volatile Memory ICs are those that lose data stored in them once they are disconnected from the power supply.
Non-volatile Memory ICs are Memory ICs that can keep data stored in them even after disconnecting power.
1. DRAM IC
DRAM refers to Dynamic Random Access Memory. A DRAM IC is a type of random access memory chip that stores volatile data in memory cells.
Where to use DRAM IC
You use DRAM ICs in computers to store data required by a computer processor to function.
Components in DRAM IC
A DRAM IC consists of memory cells in a rectangular configuration.
Each memory cell has a capacitor and a transistor.
The capacitor stores the data, with each holding a single bit of data.
The transistor switches electrical power to the capacitor.
DRAM memory circuit
Advantages of DRAM IC
- It has a simple design given only one resistor is needed.
- It has high-density levels.
- You can delete and refresh memory in a DRAM IC at the same time a program is running.
- The cost of DRAM ICs is relatively low.
- You can store more data with a DRAM IC.
Disadvantages of DRAM IC
- Memory in a DRAM IC is volatile.
- Manufacture of DRAM ICs is complex.
- DRAM IC is slower than SRAM IC.
- DRAM ICs consume more power.
- DRAM ICs require refreshing of the data stored in the memory cells.
How a DRAM IC Works
Memory cells in a DRAM IC are in rows and columns. Each memory cell consists of a transistor and a capacitor.
You can send a charge through a particular column to trigger the precise transistor.
In the case of write procedure, row lines determine the capacitor’s required state.
In the read procedure, it is the sense-amplifier that determines the charge level in a capacitor.
A charge of less than 50% is read as a “0”. On the other hand, a charge of more than 50% is interpreted as a “1”.
Based on the order of rows accessed, there is a counter that traces the refresh sequence.
2. EEPROM IC
EEPROM is an acronym for Electrically Erasable Programmable Read-Only Memory.
An EEPROM IC is a non-volatile memory chip that allows you to erase and write programs on it.
Data is stored in an EEPROM IC in minimal quantities.
Where to use EEPROM IC
You use an EEPROM IC in the following instances:
- To store configuration parameters in electronic devices
- To carry out dedicated functions in microcontrollers.
- To store individual information in smart cards such as bank cards.
- You find them in digital devices like temperature sensors to save data in the absence of power.
Components in an EEPROM IC
An EEPROM IC constitutes an array of floating transistors.
These transistors are arranged as cells of two transistors: the storage transistor and the access transistor.
EEPROM Memory IC Circuit
Advantages of an EEPROM IC
- The erasure process is immediate. It takes place electrically.
- You can erase a byte of data or the chip in totality.
- You carry out the erasure procedure without having to remove it from the circuit board.
- You can program an EEPROM IC many times.
Disadvantages of EEPROM IC
- To enable read or write process on an EEPROM IC, you require separate voltage values for each.
- There is a limit to the duration an EEPROM IC can hold its stored data.
- EEPROM ICs are costlier than alternatives like EPROM ICs.
How EEPROM ICs work
An EEPROM IC’s memory cell contains two transistors with field effect: the storage transistor and the access transistor.
The access transistor carries out the memory cell’s operation while the storage transistor stores the data.
The storage transistor has the floating gate, which captures electrons altering the characteristics of the cell.
When electrons are trapped in the floating gate, a cell is erased.
3. eMMC IC
eMMC stands for embedded Multi-Media Card.
An eMMC IC is a memory chip composed of flash memory and controller integrated into a device’s circuit board.
Where to use eMMC IC
eMMC ICs are in portable electronic devices such as smartphones, tablets and digital cameras.
Components in an eMMC IC
An eMMC IC chip comprises two major components: the flash memory and the flash memory controller.
The flash memory is a non-volatile memory storage medium that can allow erasure and reprogramming.
The flash memory controller acts as the data manager to the flash memory enabling communication within the multi-media card.
Advantages of eMMC IC
- It lessens the workload on a device’s central processing unit, allowing it to carry out more important tasks.
- An eMMC IC consumes less power.
- With the use of an eMMC IC, you do not require extra memory slots. It allows you to stack more memory functions vertically.
- eMMC ICs are relatively cheap for their size.
Disadvantages of eMMC
- In comparison with alternatives, the data transfer rate of an eMMC IC is slower.
- The storage size in eMMC ICs is relatively small for high capacity applications.
How an eMMC IC works
The eMMC IC is made up of integrated flash memory and controller, which is embedded into a device’s mainboard.
This connectivity to the circuit board allows the eMMC IC to take over data storage functions from the CPU.
It utilizes flash memory, thus requiring little to no power to hold data.
It, therefore, frees up the main central processing unit allowing it more power and speed to execute other functions.
4. EPROM IC
EPROM is short for Erasable Programmable Read-Only Memory.
An EPROM IC is a non-volatile memory chip that can be erased with the use of UV light and reprogrammed.
Where to use EPROM IC
You will find EPROM ICs utilized in the following applications:
- In the storage of BIOS in computers to enable boot procedure.
- Older generation computers used EPROM ICs for memory storage.
Components of an EPROM IC
An EPROM IC is made of cells each with two transistors: the floating gate transistor and the control gate transistor.
EPROM IC circuit
Advantages of EPROM IC
- In comparison with other memory ICs such as EEPROM IC, it is cost-effective.
- It is reprogrammable.
- It can store and retain data in the absence of power.
Disadvantages of EPROM IC
- EPROM ICs consume high static power.
- Erasure of a single byte in is not possible.
- You cannot electrically erase an EPROM IC.
- To carry out the erasure procedure, you need to remove an EPROM IC from the device’s mainboard.
- The erasure process is time-consuming.
- There is a limit to the number of times an EPROM IC can be erased.
How the EPROM IC Works
The floating gate transistor constitutes the location of storage in an EPROM IC.
It is separated from the control gate resistor by a channel, covered by a layer of oxide, with end contacts for source and drain.
When a charge is applied, electrons are excited and pushed into the channel, acquiring a negative charge. These electrons block the floating gate transistor.
A cell sensor checks the charge level at the floating gate. Electron flow level higher than half the charge percentage is designated “1”, otherwise “0”.
Data stored is determined by the absence or presence of electrons in the channel between the two gates.
5. FIFO IC
FIFO is an acronym for First In, First Out.
A FIFO IC is a storage chip that provides temporary storage of data in a computerized system. Data stored could be in transit from one process to another or awaiting enhanced processing.
They’re useful in connecting digital devices with differing rates of data production and consumption.
Data from a FIFO IC chip is supplied in line with the FIFO logic of releasing the oldest data first.
Where to use FIFO IC
You will find FIFO ICs in communications and networking applications.
Computer networks employ FIFO ICs in network bridges and routers to hold packets of data transiting to other points of application.
Components in FIFO IC
A FIFO IC usually comprises storage and two pointers to highlight read and write.
FIFO IC circuit
Advantages of FIFO IC
- FIFO ICs prevent loss of data in the case of high-speed communication.
- There is an increased bandwidth when utilizing FIFO ICs in network connections.
- FIFO ICs allow digital circuits that operate at contrasting rates to be interconnected.
- In data streams, FIFO ICs make it possible to carry out timing corrections.
Disadvantages of FIFO IC
You find FIFO ICs are unable to distinguish packets of data based on their service class.
This way, data transmitting in short bursts will be given priority over other data flows.
How a FIFO IC Works
A FIFO ICs works in a circular queue with two pointers: the read pointer and the write pointer.
Both pointers/address registers are usually at the initial location of memory and the queue for FIFO identification: empty.
The FIFO IC will trigger an empty signal immediately the read pointer reaches the write address register.
The write pointer’s arrival at the read address register causes the FIFO IC to signal adequately.
6. FRAM IC
FRAM is short for Ferroelectric Random Access Memory.
A FRAM IC is a memory IC that encompasses the speed of dynamic RAM alongside the non-volatility aspect of ROM.
It attains non-volatility by utilizing a ferroelectric film instead of a dielectric one.
Where to use FRAM IC
You will find FRAM ICs employed in the following:
- FRAM ICs are used in banking and ticketing machines to hold transactional history and provide backups.
- FRAM ICs are embedded as storage into an industrial microcontroller.
- You will find FRAM ICs in digital cameras where they provide correct value and initial setting.
- Measurement devices employ FRAM ICs for correct value and parameter setting.
Components in FRAM IC
A ferroelectric RAM IC’s memory cell is composed of a metal oxide semiconductor transistor and a ferroelectric capacitor.
FRAM IC circuit
Advantages of FRAM IC
- FRAM ICs have faster writing performance
- With FRAM IC you can perform more write and erase cycles
- FRAM ICs retain data even in no-power situations
- FRAM ICs have high endurance levels
- FRAM ICs have a low power consumption
Disadvantages of FRAM IC
- You find FRAM ICs have a lower density compared to dynamic RAM.
- FRAM ICs have a high cost.
- FRAM ICs are limited in terms of capacity.
How FRAM IC Works
Ferroelectric material in a FRAM IC contains spontaneous polarizable crystal, with two reversible states on the application of an electric field.
Application of an electric field to the crystal causes the central atom to move in the field’s direction.
Movement of the atom causes it to break through an energy barrier resulting in a charge breakdown.
This breakdown causes the internal circuits to react by setting the memory.
Removal of the electric field maintains the atom in a polarized state giving the material non-volatile property.
This preserves the memory state.
7. NAND Flash IC
A NAND Flash integrated circuit is a non-volatile storage type that retains data in the absence of power.
Where to use NAND Flash IC
You will find NAND Flash IC useful in mass storage devices like USB flash drives, SD cards, MP3 players and SSDs.
Modern CPUs use NAND Flash IC for firmware storage before reverting to SRAM on power-up.
Components in a NAND Flash IC
NAND Flash ICs are composed of memory cells made up of floating gate transistors with the control and floating gate.
NAND IC circuit
Advantages of NAND Flash IC
- The NAND Flash IC is cost-effective at the byte level in comparison with other memory ICs.
- They have high storage capacity considering their small size.
- You experience faster read and write times with NAND Flash ICs.
- NAND Flash ICs consume less power.
- They are durable as they are less prone to damage.
Disadvantages of NAND Flash IC
- NAND Flash ICs fail after performing write/erase cycles over time.
- Many lack a mechanism for write-protection.
- NAND Flash ICs are corruptible, leading to loss of data stored in them.
How a NAND Flash IC Works
To store data, a NAND Flash IC relies on electric circuits and saves the data as blocks.
A voltage is applied to the control gate to program a single cell. It causes electrons to move towards the gate.
The floating gate traps the electrons within the poly-silicon substrate. They remain here during normal conditions of operation.
Detaching power from a NAND Flash IC causes the control gate to deploy an extra charge to the memory cell. This way, data stored before cutting off power is kept.
For the erasure process, the control gate is grounded with the application of a voltage to the poly-silicon substrate.
8. NOR Flash IC
A NOR Flash IC is a non-volatile storage type differing with the NAND type on purpose and architecture only.
The NOR Flash IC is preferred in code execution due to its function of random access.
Where to use NOR Flash IC
You will find the NOR Flash IC useful in the following instances:
- NOR Flash ICs are applied in memory devices for storing and running code in small quantities.
- Due to its fast read capabilities, you will find NOR Flash ICs in embedded designs.
- BIOS chips utilize NOR Flash ICs.
- NOR Flash ICs are implemented in set-top boxes and cellular handsets.
Components in NOR Flash IC
A NOR Flash chip is composed of memory cells with each made up of the floating gate resistor.
The floating gate resistor has two gates: the control gate and the floating gate.
The floating gate is surrounded by an oxide layer that acts as an insulator.
NOR Flash memory
Advantages of NOR Flash IC
- In comparison with the NAND Flash IC, the NOR Flash IC has faster reading speeds.
- The NOR Flash IC can access memory in bytes rather than blocks.
- You can access data randomly with a NOR Flash IC.
Disadvantages of NOR Flash IC
- They are expensive.
- It takes longer to erase and write data.
Working of a NOR Flash IC
During the reading process, a voltage is applied to the control gate. This voltage should be low enough to maintain the charge level at the floating gate.
However, it should be high enough to be easily differentiated from an uncharged floating gate.
The charge determines the conductivity of the oxide layer enabling its passage through the channel if high enough.
The current transiting the channel is deciphered as binary information constituting the data stored.
9. NVRAM IC
NVRAM is a contraction for Non-Volatile Random Access Memory.
An NVRAM IC is a RAM chip with the ability to retain its stored data even in the absence of power.
Where to use NVRAM IC
You will find the NVRAM IC useful in computers as it provides CMOS (Complementary Metal-Oxide Semiconductor) storage.
It provides the storage location for the BIOS settings, including the date and time.
Components in an NVRAM IC
An NVRAM IC is known for the floating gate MOSFET (metal-oxide-semiconductor field-effect transistor).
Earlier NVRAM ICs were characterized by the presence of a rechargeable battery to maintain the power supply to the static RAM.
Advantages of NVRAM IC
- They are suitable for applications that require fast read and write functions and utilizing non-volatile memory are well supported by the NVRAM IC.
- An NVRAM IC’s performance is above and beyond other non-volatile memory chips.
- NVRAM ICs have less power needs as they have less moving parts.
Disadvantages of NVRAM IC
- Rewriting information on NVRAM ICs leads to their deterioration and eventual failure.
- NVRAM ICs write in large blocks which is problematic for many computers to address.
- It is limited in terms of performance lacking the random addressability of traditional RAMs.
How NVRAM IC Works
The floating gate transistor employs an oxide layer as an insulator for its floating gate terminal.
Application of a charge will cause the floating gate switch to convert the transistor from a binary one or zero.
To open the gate, a high voltage to overcome the channel barrier needs to be applied. Otherwise, the state of the transistor remains unchanged.
If so, the NVRAM IC retains the data characterized by the binary digits’ composition.
10. SRAM IC
SRAM refers to Static Random Access Memory.
An SRAM IC can hold onto its memory data with a continuous supply of power. It does not need to refresh, like in a DRAM IC.
Where to use an SRAM IC
- An SRAM IC is suitable as cache memory for computers.
- They are suitable for video cards as part of the RAM digital-to-analogue converter.
- SRAM ICs find use in microprocessors to store registers.
- Automotive electronics utilize SRAM ICs for memory storage.
Components of an SRAM IC
An SRAM IC has six metal-oxide silicon transistors.
Four transistors from two pairs of cross-coupled inverters and store a single bit.
The other two transistors control storage cell access.
Advantages of an SRAM IC
- Unlike DRAM ICs, SRAM ICs do not require refreshing to hold onto memory data.
- SRAM ICs provide better performance than DRAM ICs.
- SRAM ICs are best for creating caches that are sensitive to speed.
- They have low power needs.
Disadvantages of an SRAM IC
You find the following drawbacks in using SRAM IC:
- SRAM ICs are costlier than DRAM ICs.
- They lose data when power is cut.
- SRAM ICs have a low capacity for storage.
- Design for an SRAM IC is complex.
How an SRAM IC Works
Once a cell is selected, the value to be written is stored in the four cross-coupled inverters.
Each cell can be addressed individually since the configuration is in a matrix.
The Word Line allows access to the memory cell, controlling the two transistors that direct access.
The access control transistors determine the connection of the bit lines to the cell.
These bit lines are used for data transfer during reading/write operations.
Are there Limitations of Memory Chips?
Yes, there are.
You will find several limitations with memory chips. Some of them are explained below.
Memory chips such as dynamic RAM ICs have volatile memory and lose data in the event power is cut off.
You will find memory chips consume considerable high amounts of power, such as the EPROM IC.
Memory chips like Flash Memory IC have a limit to the duration they can hold stored data.
While some are affordable, you will find some memory chips costly like the NOR Flash IC.
While some memory chips can be erased and written, there’s a limit to the write-erase cycles you can carry out.
Many memory chips lack a mechanism for write-protection.
Non-volatile RAM ICs write in large blocks which poses a difficulty for computers to address.
You will find some memory chips provide better performance with low storage capacity such as the SRAM IC.
Which Technology did Memory ICs Replace?
The transistor is the primary building block of memory integrated circuits, developed from semi-conductor material.
Semi-conductor materials possess resistance properties between that of a conductor and an insulator.
Transistors are used in memory integrated circuits to regulate the current or voltage needs for electronic signal switching.
Before the transistor, the vacuum tube or electron tube was used for amplification of an electronic signal.
Vacuum tubes were composed of electrodes responsible for controlling the flow of electrons.
Vacuum tubes fell out of favour paving the way for the use of transistors because of the following reasons:
Vacuum tubes were large and not suitable for use in smaller devices. Transistors are tiny and you can fit hundreds of them on a memory chip.
The cost of making vacuum tubes was high, and transistors having low production cost were favoured.
Transistors consume less power compared to vacuum tubes with comparatively less wastage of heat.
The small size of transistors made them easy for use in portable devices, a feature lacking in vacuum tubes.
Vacuum tubes require a supply of high voltage power and therefore unsuitable for small voltage devices such as memory chips.
Transistors, unlike vacuum tubes, have high efficiency in small-signal circuits.
Vacuum tubes have low voltage gain with high input impedance compared to transistors with high and low characteristics, respectively.
What do Memory ICs do?
Memory integrated circuits are chips used for storage purposes in electronic devices. They store data, information or a program useful for a computer or other electronic devices such as a mobile phone.
How do you Test Memory IC?
You carry out a memory IC test for a variety of reasons.
This includes catastrophic failure of a memory chip, electrical wiring problems and improper insertion of memory chips.
You can test an integrated memory circuit by use of the following three sequential approaches:
· Data Bus Test
You first test the wiring of the data bus. This helps you to determine whether values placed on the data bus by the processor are received by the memory IC correctly.
You test this by writing as many data values as possible and verifying their successful storage by the memory chip.
Otherwise, you can examine the bus one bit after another. The test is successful if you can set each bit of data to 0 and 1, separately from other bits of data.
You carry out an independent test of each bit by conducting the “walking 1’s test.” You perform this test by writing a data value and verifying by reading it back for all set values.
The test is called so since you set a bit of data to 1 and “walk” it through the whole data word. The data values you will test should be equal to the data bus width.
· Address Bus Test
You only carry out the address bus test upon successfully carrying out the data bus test. This is because the address bus test assumes a non-defective data bus.
You need to isolate each bit address in your test. This you do by establishing the ability to set each address pins to 0 and 1 without impacting the other addresses.
You will be faced by the challenge of overlapping locations in an address bus test.
As such, you must ensure no other address has been overwritten after carrying a write procedure on one.
To confirm no overlapping of memory locations within the device, you write an initial data value at each power-of-two offset.
You then write a new value to the offset of the first test. Confirm the initial data value is stored at every other offset that is of the poser-of-two.
Establishing a different location with the new data value indicates a problem with the current address bit.
If you find no overlapping, you carry out the same procedure for the other offsets.
· Device Test
You carry out the device test upon confirming the working of the address bus and data bus wiring.
Testing the memory chip requires you to establish whether every bit can hold either a 0 or 1.
To carry out a complete test, you have to write and verify each location of memory two times.
Whatever data you chose for the first test, you have to invert the value for the second test.
What are the Characteristics of Memory IC?
The characteristics of memory ICs include:
Memory IC capacity is expressed in word size stylized as bytes, where 1 byte is equal to 8 bits.
· Method of Access
This refers to the order in which stored data on a memory chip can be accessed. Access can be random, serial or semi-random.
In random access, there is no order in which memory data is to be accessed.
Serial access only allows locations of memory to be accessed sequentially.
Memory devices with semi-random access constitute tracks with read and write capabilities. These trucks can be accessed randomly. However, data within each track can only be accessed in a serial manner.
Integrated memory circuits can be categorized as erasable or non-erasable. Erasable memory chips can allow for the removal of data in them and thereafter reprogramming.
Non-erasable memory ICs are permanent once programmed.
Memory ICs can be stored in three locations, as follows:
- In a Central Processing Unit (CPU) as cache memory and registers.
- As internal or main memory such as dynamic RAM IC from where they can be accessed by the CPU
- As external or secondary memory like SSDs not directly accessible to the CPU
· Transfer Unit
It is the maximum number of bits that can be written or read into a memory chip. Main memory is limited to word size while secondary memory is larger and in block form.
You can define performance based on the following key aspects:
- Memory cycle time – This is specific to RAM ICs. It is the total access time, plus any extra time spent before the second access begins.
- Access time – Time it takes to complete and write or read process by memory IC for RAM chips. When it comes to non-random access chip memory, this is the time it takes to position a write or read head at a suitable location.
- Transfer rate – It is the speed at which you can transfer data to or from the memory chip.
Volatility refers to a memory IC’s ability to hold or retain data when power is cut off. Volatile memory ICs are unable to hold data in the absence of power. Non-volatile memory chips retain data even when power supply is terminated.
How is Memory IC Made?
Memory ICs are produced in clean environments to avoid destruction by small dust particles due to their intricate circuitry.
This is possible through continuously filtering and circulating air into the rooms and use of specialized clothing.
In order to produce memory chips you need to understand the following steps.
Silicon ingots are sliced into polished wafers of about thirty centimeters diameter and thickness of about half a millimeter.
The wafers are blanketed with a glass layer and nitride layer.
Exposing the wafer to oxygen at high temperatures of about 1652 degrees Fahrenheit for about an hour forms the glass.
The memory chip’s circuitry is laid out on the wafer, after being developed, tested and simulated on computers.
Each circuit layer is masked by a glass photo-mask. A photo-mask is a bulleted opaque plate. The holes on the mask allow light passage in a predetermined pattern in a process called photolithography.
The photo-masks describe the individualities of the transistor, resistor and capacitor in order to complete the integrated circuit. They also provide the pattern for the circuit for every layer.
A thick liquid that is sensitive to light called photoresist is coated uniformly on the wafer. Parts of the wafer are exposed to UV light through the photo-mask exposing the photoresist. Exposed photoresist changes chemically and removed.
The unprotected nitride layer portion is removed by application of a plasma dry glass or wet acid. This allows the application of integrated memory chips to be placed on the wafer.
A layer of insulating glass is added onto the wafer and contact points for the circuit elements defined.
Thereafter, a thin aluminum layer is etched onto the entire wafer. Another mask is applied to the layer to create circuit paths by forming a network of thin metal wires.
To protect the wafer from contamination while assembling, an insulating layer called the passivation layer is added.
The layer consist of silicon nitride and glass.
The terminals covered by the passivation material are exposed to be connected to the pins on the chip’s package.
This marks the completion of the formation of the integrated circuit.
After successfully testing all the ICs on the wafer, it is cut into singular chips by use of a die saw. This singular chips are what is called a die.
The die then undergoes encapsulation where the die’s lead frames are attached to mold plates before being heated.
Molten plastic is molded around the die to form its package, and the lead frames pressed before being cleaned.
The lead frames are submerged in a tin and lead solution a process called electroplating.
Lead and tin ions migrate to the charged lead frame creating a uniform plated deposit, improving die conductivity.
This also provides a surface that is clean to allow the die to be mounted.
The chips are separated from the frames upon lading them into tri and form machines. They are then packaged into antistatic tubes for transit to test area.
Burn-in testing tests the chip for its performance under exaggerated stress conditions. This identifies and rids chips that will prove unreliable after limited usage.
Successful memory chips go through a final inspection before being sealed for assemblage.
How does Memory Integrated Circuits Store Data?
Memory Integrated Circuits store data in memory cells which is a chips primary building block. A memory cell is a minuscule circuit composed of a capacitor and one or more transistors depending on type.
The transistor acts as an amplifier or switch to activate data whereas the capacitor stores data as a charge.
The capacitor can either be charged or discharged with the two states indicating the binary values of 0 or 1. This represent a unit of data referred to as a bit.
Memory cells are arranged in rows, with a bit line formation connecting to a memory address called a word line.
Through the address, location for storage of data can be identified. The word line provides an electrical path for activation of memory cells in a row for write or read procedure.
Electrical signals identifying the location of a cell in an array initiate data access. These electrical signals are referred to as row address strobe (RAS) and column address strobe (CAS).
Storage of a charge in a capacitor from a selected cell will signal the transistor to conduct. This will cause transfer of the charge to the bit line that is connected. This results in a minimal increase in voltage that is read as binary value 1.
How do you Read Memory ICs?
You can read data from a memory IC in the through the following process. The three system buses are involved as follows:
- Set the location memory address on the address bus.
- Request a read operation by setting to high, the read/write wire of the control bus.
- You should set address valid control wire to high.
- The indicator for valid address and value for address bus will activate once you fit memory IC alongside select wire.
- Data on the memory location will be trans-located to the data bus.
- Using a register in the microprocessor, you can read the value in the data bus.
- Ultimately set the read/write wire, address valid wire and the chip select wire low.
Can you Erase Data from Memory ICs?
Yes you can.
Some memory ICs allow erasure of data from them.
These include Memory ICs such as the EPROM IC, EEPROM IC and the Flash Memory.
Which Format does Memory Integrated Circuit Store Data?
Data storage in memory IC
An integrated memory circuit stores data in the form of a charge.
The charge is stored by a capacitor in a memory cell.
The memory cell is composed of a transistor and a capacitor. The number of transistors varies with the type of memory integrated circuit.
The transistor acts as a switch or amplifier for activating charge stored in the capacitor.
How many times can you Erase Data from Memory IC?
The number of times you can erase data on a memory IC depends on the type of chip.
Memory ICs like the EPROM IC, EEPROM IC AND the Flash Memory IC allow you to erase data many times.
They will however, not endure unending write-erase cycles and will lose the ability to hold data in the long run.
Memory ICs like the PROM IC cannot be erased. Once data has been written onto them it is permanent.
How will you know Memory IC is damaged?
You can identify damage to memory chips tin the following ways:
You can tell a memory IC is damaged if or when it has broken contact points.
If a memory IC is physically bent or punctured, you should be able to tell it is damaged.
For integrated memory circuits such as RAM ICs, damage will manifest through spontaneous reboots of the computer.
Program failures during launch are another indicator of damage to the memory IC that you can use.
Appearance of a blue screen on startup can inform you on damage to a memory integrated circuit.
Which Industries use Memory ICs?
You find various industries using memory integrated circuits as follows.
- The computer industry utilizes memory ICs such as dynamic RAM IC for usage as main computer memory.
- You find application of memory ICs in the entertainment industry with the use of ROM ICs in electronic musical instruments.
- The automotive industry employs EEPROM ICs in their anti-lock braking system, air bags and radios.
- The consumer electronics industry also utilizes EEPROM ICs in set-top boxes, washing machines and televisions.
- You find EEPROM ICs being used in the financial industry in the making of bank payment.
- Flash memory ICs have been applied in the entertainment industry in gadgets such as portable media players.
- You find Flash Memory ICs application in the mobile phone industry as storage for smartphones.
- The medical industry employs use of non-volatile RAM ICs in the manufacture of medical equipment.
- The medical industry employs use of non-volatile RAM ICs in the manufacture of medical equipment.
- You find application of NVRAM ICs in the aviation industry with their use as storage chips in spacecraft.
- You find static RAM IC being applied in the computer industry as main memory for multimedia computers and workstations.
Is there difference between Microprocessor and Memory IC?
Yes there is.
While both are integrated circuits, they are integrated to perform different functions.
A microprocessor is an integrated circuit that amalgamates a computer’s central processing unit functions.
A microprocessor is composed of an arithmetic logic unit (ALU), a control unit and a register array.
It is able to perform logical and arithmetic operations through the ALU.
A microprocessors control unit regulates the data flow in the computer.
The register array has registers identifiable with letters alongside an accumulator.
Microprocessors are identified with their clock speed and the number of bits they use per instruction which they can process.
Memory ICs are chips used for data storage and code processing.
Data stored in memory chips can either be permanent or temporal depending on the memory chip type.
Memory ICs hold data temporarily through random access memory (RAM).
Permanent data in memory ICs is held through Read Only Memory (ROM) ICs.
How best can you Package Memory IC?
You find various packaging configurations of Memory ICs as provided below.
· Dual Inline Pin Package (DIP)
This packaging type is characterized by a rectangular chip attached with pins along the long sides.
It was used as a DRAM IC package for many of the older generation computers. DIPs were manufactured in both Page and Fast Page Modes and are presently outdated.
· Single Inline Pin Package (SIPP)
This packaging configuration was a modification of the DIP in order to allow increased memory density.
Turning a DIP chip sideways, it extended all the leads on one side and parallel to the chip plane. SIPPS are currently out of date and were produced in Page and Fast Page Modes.
· Single Inline Memory Module (SIMM)
With this package you find multiple chips of DRAM DIP mounted on a small circuit board. This circuit board has a card edge connector that is constructed to fit a socket on the motherboard.
There are two form factors of SIMM you will find.
These SIMMs are obsolete although still available. They are too slow and small to be put in current usage, though find use in a number of laser printers.
Produced in Page Mode and Fast Page Mode, they found application in 286, 386 and 486 systems.
These SIMMs were released in Fast Page Mode, EDO and BEDO forms.
Though presently outdated, they are applicable in some later computer systems and for memory expansion in select laser printers.
Dual Inline Memory Module (DIMM)
These modules have connectors on both sides of the circuit board. They are available in a variety based on the number of pins.
You will find DIMMs with pins ranging from 100-232 depending on the type. Some have different keying notch positions to discourage interchanging.
How do you Specify Memory IC?
When selecting memory chips, you need to consider specifications relating to a memory chip’s efficiency and speed.
The following parameters help you:
· Cycle time
This refers to the time required to complete one read/write procedure and the resetting of the chip for another cycle.
· Data rate
This represents the number of transferrable bits within a chip in a second. Data rate is expressed in hertz (Hz).
This is the quantity of data an integrated memory circuit can process within a determined time frame. It is expressible in bits per second (bps or b/s), bytes per second (Bps or B/s) or hertz (Hz).
· Access time
This expresses the time taken from when the CPU calls for data to when it receives it in nanoseconds.
How can you Identify Various Types of Memory?
There are many ways that you can use to identify a memory chip.
- You can use the chip serial number to establish what type of memory chip you have.
- Other chips allow you to know the type from their packaging.
- For RAM ICs, you can look at the length of the chip and the position of notches to help identify a memory chip.
- The presence or absence of heat shields is also a marker for helping you identify a particular chip.
- The number of pins on a memory integrated circuit can lead you on the chip type.
- A memory chip’s build can also guide you on the type such as an EPROM ICs quartz window.
What is Semi-conductor Memory?
A semi-conductor memory is a storage device of electronic data that is fabricated on an integrated circuit. The integrated circuit is made from semiconducting material, often silicon.
It is used for storing digital data such as computer memory.
Semiconductor memory is of two types: volatile and non-volatile memory.
Semi conductor memories
Volatile memory refers to that which is temporal and lost when power supply is interrupted.
It is faster and less expensive compared to non-volatile memory.
Non-volatile memory is of a permanent nature and is preserved even in the absence of power.
What are the Quality Standards for Memory Chip?
There are a number of features you will find that are used to determine the quality standards of memory chips.
The standards used are specific to the type of memory chip.
Standards of memory devices you can find include.
- SMD 5962-08208: as a standard for a microcircuit FIFO IC.
- DESC-DWG-5962-01516: 8-bit PROM microcircuit memory device
- MIL-M-38510/201: Microcircuits, 512-Bit, Programmable Read-Only Memory (PROM)
- MIL-M-38510/224: Microcircuits, Ultraviolet Erasable Programmable Read-Only Memory (EPROM)
- MIL-M-38510/227 › Microcircuits for 384 BIT, Electrically Erasable Programmable Read-Only Memory (EEPROM)
- MIL-M-38510/240: Dynamic Random Access Memory (DRAM) microcircuit memory device
- DESC-DWG-5962-00536: 8-bit SRAM microcircuit memory chip
- MIL-M-38510/289: Static Random Access Memory (RAM) Microcircuits
- BS EN 61964 as a standard for Memory chip devices’ pin configurations
What are the Technological Advancements in Memory Chip Industry?
You will find that there are marked advancements in technology in the memory chip industry. These are primarily driven by the need for chips with higher densities, efficiency levels and faster speeds.
Currently, many chip makers are working to improve the NAND Flash Memory IC. This is attributed to deficiencies you will find in Flash Memory ICs as follows.
Flash Memory chips have exhibited an increase in the frequency of errors while reading data.
Flash Memory ICs have shown a decrease in their endurance and retention of data.
It is on these premises that the 3D NAND Flash Memory has been forwarded.
There have been two approaches in the functionality of 3D NAND Flash Memory.
i. Use of Floating Gates
Floating gate in memory IC
This uses the same principle of NAND Flash Memory ICs.
The floating gate traps charges between the channel and the control gate. However, there is use of Multi-Level Cells (MLC) thus achieving better endurance levels.
A Multi-Level Cell (MLC) is a memory cell that is capable of storing more than a single bit of data.
ii. Use of Charge Trapping Memory
This is done through the use of Charge Trap Flash (CTF) technology. In this case, the charges are stored in “trapping” centers. These centers are separated from the channel by an oxide layer.
Charge trap flash
The “trapping” centers are made of silicon nitride which is an insulator. This improvement ensures there is no memory wear that could be caused by short circuit currents.
Moreover, it improves efficiency levels of the memory chip.
How does On-chip Memory and Off-chip Memory compare?
On-chip memory refers to memory that is incorporated onto the same integrated circuit as the processor and its peripherals.
This way, the processor has direct access to the memory location.
Off-chip memory refers to memory not physically based on the same integrated circuit as the processor. This means the memory location is external to the IC.
What Determines Speed of Memory Chips?
The speed of memory chips is determined by a memory chip’s access time and data rate.
Access time describes the time period from when a processor calls for data to when it receives it in nanoseconds.
Data rate denotes the number of bits that can be transferred within a chip in a second
How much Data Can Memory IC hold?
You will find that a memory IC can hold data from a few megabytes to gigabytes.
The amount of data a memory chip can hold depends on the memory type and its function.
Volatile memory ICs have the capacity to hold less data when compared to non-volatile memory ICs.
You can attribute this to the inability of volatile memory chips to hold data with no power.
Volatile memory chips are utilized well as storage for cache memory.
Non-volatile memory chips applied mostly as external storage devices can hold thousands of megabytes.
The NAND Flash Memory IC is a fitting example of memory chip that has very large storage capacity.
What is Memory Chip Address?
A memory chip address refers to a discrete number that is assigned to every byte of data in a memory chip.
This number is helpful to the processor for tracking data stored in a chip’s memory location.
What is the difference between Address Bus and Data Bus in Memory Chip?
Address bus vs data bus
An address bus carries address information from the processor to the memory.
When the processor needs data from the memory, it deposits the data address onto the address bus.
The address bus is unidirectional and determines the number of locations in a memory.
A data bus transmits data or instructions between the memory and processor.
It is bidirectional meaning it can carry data to and fro.
What is the Internal Organization of Memory Chips?
It refers to the arrangement of memory cells in a memory chip.
Memory cells, each storing a single bit of information are organized in a matrix in a memory chip.
A row of memory cells comprises a memory word with a common connection to a line called word line.
Normally, there are two lines that connect memory cells.
We refer to these lines as bit lines.
To drive the word line, an address decoder is used.
Once the address bus identifies address, it will enable a single word line.
Normally, the sense or write circuit connects the bit lines to both the data output and input.
During Read procedure, Sense/Write circuit reads the data stored in the word line selected cells. It then transports this data to the data line output.
During Write procedure, the circuit (Sense/Write) receives data storing it in the cells belonging to the selected words.
Memory chips are organized in words and bits. So a chip with 16 words, each with 8 bits, is stylized 16×8.
Each Sense/Write circuits’ data input and output lines are in one bidirectional data line.
It will reduce the pin count you may need.
Thus, 16 words require a size 4 address bus.
A Chip Select (CS) line and a pair of control lines are provided alongside the data and address lines.
The Chip Select line is handy in selecting a particular chip in any memory structure with multiple chips.
What should you consider before buying Memory Chips?
When purchasing memory chips, you need to consider the following aspects.
You purchase a memory chip based on where you need to employ it. To improve your computer’s performance, you may need to buy a dynamic RAM IC.
To expand your storage, you can buy a NAND Flash Memory IC.
You can determine a memory chip’s performance by considering its read/write speed. This is how quickly it is able to read/write data.
3) Write/Erase Cycles
A memory chip’s write/erase cycles refers to the number of times a memory chip can be overwritten before wearing out and eventually failing.
4) Mean Time Before Failure
This measures a memory chip’s reliability. It refers to how long you can use a memory chip before it exhausts its lifespan.
5) Storage Capacity
You purchase memory chips to meet your extra storage needs. You therefore have to know how much of extra storage you actually need when purchasing a memory chip.
Clearly, the structure and specifications of memory chips are quite detailed.
However, when you consider everything highlighted in this guide, choosing a suitable memory IC for your applications will be easier.
At Rantle, we are here to help you get the best memory ICs – contact us now for free consultations.