솔리드 스테이트 드라이브 플래시 메모리: 작동 방식 및 데이터 복구

솔리드 스테이트 드라이브 플래시 메모리의 이해

솔리드 스테이트 드라이브 플래시 메모리 is non-volatile NAND storage technology that most modern SSDs use to retain digital data without power. Unlike traditional hard disk drives (HDDs), which store data magnetically on spinning platters, SSDs use electronic memory cells to provide fast access without mechanical movement.

This technology improves storage performance, but it also introduces important differences in endurance, file deletion, and data recovery. Understanding these differences can help you choose an SSD and protect valuable files.

This guide explains how NAND flash works, what SSD controllers do, and why TRIM affects deleted files. For device-specific information, explore our SSD solutions and recovery guides.

목차

Solid State Drive Flash Memory: Quick Facts

Property

설명

기술

Non-volatile NAND flash memory

주요 목적

Store digital information without continuous power

일반적인 기기

SATA SSDs, NVMe SSDs, portable SSDs

Storage structure

Cells, pages, and blocks

Main components

NAND chips, controller, firmware

NAND types

SLC, MLC, TLC, QLC

Related technologies

FTL, wear leveling, garbage collection, TRIM

Primary limitation

Finite write endurance and controller-dependent access

주요 차이점: Flash memory is the storage medium, while an SSD is the complete device that manages and exposes that storage to a computer.

Understanding SSD Flash Memory in Simple Terms

Think of an SSD as a storage system with two main responsibilities.

The NAND flash chips hold the information. Meanwhile, the SSD controller decides where to place it and how to retrieve it efficiently.

For example, when you save a document, Windows sends data to the SSD through its storage interface. The controller selects suitable flash locations and records where the information resides.

Later, when you open the document, the controller uses its mapping information to locate and return the stored data.

This simplified explanation highlights an important difference: the file address that Windows sees does not necessarily match a fixed physical NAND location.

As a result, SSDs can move data internally without changing the file paths shown in Windows.

SSD-internal-architecture

How Does Solid State Drive Flash Memory Work?

그리고 솔리드 스테이트 드라이브 플래시 메모리 system combines electronic storage with controller-managed data placement.

NAND Cells Store Information

NAND flash cells represent information through different electrical charge states. The SSD reads those states to distinguish stored values.

Manufacturers organize cells into larger structures:

  • 셀: Stores one or more bits.
  • Page: Groups cells into a unit for reading and programming.
  • Block: Contains multiple pages and serves as an erase unit.

Importantly, NAND generally programs data at the page level but erases it at the block level.

Therefore, updating an existing file does not necessarily overwrite its previous physical location immediately.

The Controller Maps Logical and Physical Addresses

The Flash Translation Layer (FTL) connects logical block addresses with physical NAND locations.

A typical write follows this sequence:

  1. Windows sends a write request to the SSD.
  2. The controller receives the logical address and data.
  3. The FTL selects an appropriate physical location.
  4. NAND cells store the information.
  5. The controller updates its mapping records.

When Windows requests the data later, the controller uses those records to identify the correct location.

This process helps the SSD manage its physical storage independently of the operating system.

SSD-Flash-Translation-Layer-mapping-logical-block-addresses-to-physical-NAND-flash-memory

Wear Leveling and Garbage Collection Manage Space

Because NAND cells support a finite number of program/erase cycles, controllers distribute writes across flash blocks through 웨어 레벨링.

Additionally, garbage collection consolidates valid information and reclaims blocks containing obsolete pages.

Both mechanisms support long-term performance and endurance.

However, they also explain why deleted data may become inaccessible even without new user files directly overwriting its former logical addresses.

TRIM Identifies Unneeded Data

When Windows deletes a file, it may send a TRIM notification identifying logical blocks that the file system no longer needs.

The SSD can then invalidate those mappings and prepare the underlying space for reuse.

Consequently, TRIM can substantially reduce the possibility of recovering deleted files.

For a deeper technical explanation, read our SSD NAND flash memory guide 그리고 What Is TRIM?.

Kingston also describes NAND and SSD operation in its NAND Flash Technology guide.

Components and Types of Solid State Drive Flash Memory

An SSD combines several components, but NAND type strongly influences storage density and endurance.

Main SSD Components

The three essential elements perform different roles:

  • NAND flash: Retains user data.
  • Controller: Handles logical mapping, error correction, and storage management.
  • Firmware: Implements the rules that coordinate device operation.

Although NAND provides the storage capacity, the controller and firmware determine how the drive uses that capacity.

SLC, MLC, TLC, and QLC NAND

NAND type

Bits per cell

General trade-off

SLC

1

Higher endurance, lower density

MLC

2

Balance of density and endurance

TLC

3

Good balance for mainstream SSDs

QLC

4

Higher density, lower cell-level endurance

For instance, a TLC SSD often suits everyday operating-system workloads. In contrast, a QLC drive may offer attractive capacity for read-heavy storage.

Modern 3D NAND stacks memory cells vertically. It describes their physical arrangement, not how many bits each cell stores. Therefore, a 3D NAND SSD can use TLC or QLC technology.

Why Solid State Drive Flash Memory Matters

The practical value of 솔리드 스테이트 드라이브 플래시 메모리 extends beyond storage capacity.

성능: Electronic access eliminates mechanical seek delays. As a result, SSDs generally offer faster random access than HDDs.

Endurance: NAND cells wear gradually through program/erase operations. Manufacturers use TBW (Terabytes Written) and DWPD (Drive Writes Per Day) ratings to describe endurance expectations.

Data recovery: TRIM and internal address mapping can prevent traditional undelete methods from accessing old information.

신뢰성: SSDs resist mechanical shocks better than HDDs, but controllers, firmware, and electronic components can still fail.

For example, a laptop SSD may operate normally for years but suddenly become inaccessible because of a controller problem rather than exhausted NAND cells.

Therefore, endurance ratings cannot predict every possible failure. Regular backups remain essential regardless of the drive’s reported health.

Flash Memory vs SSD vs HDD: What's the Difference?

These terms describe different technical layers, so they should not be treated as interchangeable.

기능

플래시 메모리

SSD

HDD

카테고리

Storage medium

Complete storage device

Complete storage device

Data storage

Electronic charge states

Usually NAND flash

Magnetic platters

컨트롤러

Requires external management

Integrated

Integrated

움직이는 부품

없음

없음

예

Common example

NAND 칩

SATA or NVMe SSD

Desktop hard drive

An SSD typically contains NAND flash memory, but not every flash-based device qualifies as an SSD.

For example, USB flash drives and SD cards also use NAND storage. However, their controllers, interfaces, and workloads can differ considerably.

Likewise, NVMe describes a storage communication protocol rather than a NAND type. Both SATA and NVMe SSDs may use similar flash technologies.

For a focused comparison, see 플래시 메모리 대 SSD.

Where Can You See SSD Flash Memory in Windows?

Windows does not normally expose an SSD’s internal NAND pages, physical blocks, or FTL mappings.

However, Windows 10 and Windows 11 provide several ways to inspect the storage device and relevant settings.

Windows-11-Optimize-Drives-utility-identifying-an-SSD-as-a-solid-state-drive

디스크 관리

프레스 승리 + X 을 클릭하고 디스크 관리.

You can inspect the drive’s capacity, partitions, and file system status.

For example, an SSD might show a healthy NTFS partition, an unallocated region, or a RAW volume.

These indicators describe Windows’ logical view of the device. They do not directly reveal the health of individual NAND cells.

Optimize Drives

Windows에서 다음을 검색하세요 드라이브 조각 모음 및 최적화.

This utility identifies recognized media types and manages appropriate optimization operations.

Microsoft explains that SSD optimization uses TRIM-related operations rather than relying solely on traditional HDD-style defragmentation.

See Microsoft’s Optimize Drives documentation.

Check the Windows TRIM Setting

Open Command Prompt as Administrator and run:

fsutil 동작 쿼리 DisableDeleteNotify

For NTFS, a value of 0 means Windows has enabled delete notifications, while 1 means it has disabled them.

However, this setting does not confirm whether a particular deleted file remains recoverable.

Microsoft documents the command in its fsutil behavior reference.

Common Misconceptions About SSD Flash Memory

Several misunderstandings can lead to incorrect troubleshooting decisions.

Does TRIM Immediately Physically Erase Every Deleted File?

Not necessarily. The SSD may invalidate logical access before physically erasing NAND blocks.

Nevertheless, once the drive stops exposing the original information, ordinary recovery software cannot reconstruct it simply by scanning.

Does the FTL Guarantee Deleted-File Recovery?

No. The FTL maps logical addresses to physical locations, but it does not maintain a user-accessible backup of every file.

Furthermore, standard recovery software generally cannot inspect or rebuild inaccessible internal FTL mappings.

Does Higher SSD Endurance Mean Data Is Always Safe?

No. Higher endurance ratings relate primarily to sustained write workloads.

Controller failures, firmware errors, electrical damage, and accidental deletion can still cause data loss.

Similarly, a healthy SMART status does not guarantee that an SSD will never fail unexpectedly.

Safety: What Should You Avoid Changing?

솔리드 스테이트 드라이브 플래시 메모리 depends on several internal management mechanisms that users should not modify casually.

Disabling TRIM globally can affect normal SSD maintenance. Additionally, manual firmware changes, secure erase commands, and unnecessary formatting may introduce irreversible data loss.

If important files disappear, avoid writing new data, initializing the SSD, or running repair operations before protecting recoverable information.

For an inaccessible drive, preserve its current state and identify whether the problem involves logical structures or hardware.

Remember that a repair operation can restore file system usability without restoring missing files.

Practical Relevance: When Should You Take Action?

Most users do not need to change how 솔리드 스테이트 드라이브 플래시 메모리 operates. Windows and the SSD controller handle routine storage management automatically.

However, certain situations require different next steps:

  • Normal SSD operation: Continue regular backups and manufacturer-recommended maintenance.
  • Deleted or missing files: Check Recycle Bin, File History, and cloud backups before attempting recovery.
  • RAW or missing partition: Avoid formatting and assess whether the SSD remains readable.
  • SSD absent from BIOS/UEFI: Investigate connections and potential hardware failure before attempting software recovery.

For device recognition problems, consult our SSD not recognized guide.

If Windows still recognizes the SSD and accessible data may remain, our SSD 데이터 복구 가이드 explains the recovery process.

For supported logical data-loss scenarios, Magic Data Recovery offers a Windows scan-and-preview workflow that can help identify accessible files before attempting repairs. However, it cannot reverse completed TRIM or repair a failed SSD controller.

Using Magic Data Recovery to recover files from solid status drive

결론

솔리드 스테이트 드라이브 플래시 메모리 uses NAND cells, controller-managed address mapping, and background maintenance mechanisms to provide fast, non-volatile storage. These technologies improve performance but also influence endurance, data accessibility, and recovery limitations.

Understanding how NAND, FTL, garbage collection, and TRIM interact helps users make informed storage decisions.

For additional device guidance, explore our SSD 솔루션. When logical file loss occurs on a readable SSD, Magic Data Recovery is worth considering because its scan-and-preview workflow helps users examine accessible files without first modifying the file system.

Windows 7/8/10/11 및 Windows Server 지원

자주 묻는 질문

Is 3D NAND the Same as TLC Flash Memory?

No. 3D NAND describes how manufacturers arrange memory cells vertically, while TLC describes how many bits each cell stores. These concepts operate at different levels. Consequently, a drive can use both 3D NAND and TLC. Modern SSD manufacturers combine these technologies to improve storage density while balancing performance, endurance, and manufacturing costs.

Does NVMe Use Different Flash Memory Than SATA SSDs?

Not necessarily. NVMe and SATA describe different storage communication technologies, while NAND flash provides the physical storage medium. An NVMe SSD and a SATA SSD may use comparable TLC or QLC NAND chips. Their performance differences also depend on interface bandwidth, command handling, controller architecture, and the drive's internal design.

Can NAND Flash Memory Store Data Without Electricity?

Yes. NAND flash is non-volatile, meaning it retains information when power disappears. However, retention is not unlimited. Temperature, cell wear, storage conditions, and device design influence how long data remains reliable without power. Therefore, an unused SSD should not serve as the only long-term archive for irreplaceable information.

Can Disabling TRIM Help Recover Previously Deleted SSD Files?

Disabling TRIM after deletion cannot restore information that the SSD has already invalidated or made inaccessible. Although TRIM settings influence future delete notifications, changing them is not a reliable recovery technique. Additionally, disabling routine SSD maintenance can affect performance. Check existing backups and evaluate the affected drive without making unnecessary changes.

What Do TBW and DWPD Tell You About SSD Lifespan?

TBW describes a manufacturer-rated amount of data written to an SSD, while DWPD expresses endurance relative to drive capacity over a specified period. Both help compare drives for different writing workloads. However, neither represents an exact failure deadline. Electronics, firmware, temperature, and operating conditions also influence overall reliability.

Why Can an SSD Show Healthy Status but Still Lose Data?

SMART health indicators monitor selected device conditions, including certain errors and endurance measurements. However, they cannot predict every controller failure, firmware problem, or sudden electrical fault. Additionally, logical file deletion can occur on an otherwise healthy SSD. For this reason, backups remain necessary even when monitoring software reports good drive health.

Can Software Recover Data When an SSD Is Not Detected in BIOS?

Ordinary recovery software generally requires the operating system to access the SSD through a functioning storage interface. If BIOS or UEFI cannot detect the drive, software scanning may not be possible. First rule out connection and power problems. If detection consistently fails, a qualified recovery specialist may need to investigate controller, firmware, or hardware damage.

Jason는 15년 이상의 실무 경험을 갖춘 데이터 복구 및 기술 지원 전문가입니다. 그는 현장 사용자와 폭넓게 협력하며, 까다로운 데이터 손실 사례를 해결하고, 실수로 인한 삭제, 드라이브 포맷, 파일 시스템 손상, 파티션 손실, 시스템 장애 및 기타 긴급 복구 상황에 대한 실용적인 복구 솔루션을 제공해 왔습니다. 또한 백업 및 복원, 파일 복구, 재해 복구 분야에서도 전문성을 갖추고 있으며, 안전하고 신뢰할 수 있으며 기술적으로 정확한 지침을 제공하는 데 중점을 두고 있습니다.