25LC256-I/SM

Product Overview

Category: Integrated Circuits (ICs)

Use: The 25LC256-I/SM is a serial EEPROM (Electrically Erasable Programmable Read-Only Memory) that provides non-volatile storage of data. It is commonly used in various electronic devices for storing configuration settings, calibration data, and other small amounts of information.

Characteristics: - Low power consumption - High reliability - Small form factor - Easy to interface with microcontrollers - Wide operating voltage range

Package: The 25LC256-I/SM is available in an SOIC (Small Outline Integrated Circuit) package. This package offers a compact size and allows for easy integration into circuit boards.

Essence: The essence of the 25LC256-I/SM is its ability to provide non-volatile memory storage in a small and reliable package, making it suitable for use in a wide range of electronic devices.

Packaging/Quantity: The 25LC256-I/SM is typically sold in reels or tubes, with each reel or tube containing a specific quantity of ICs. The exact packaging and quantity may vary depending on the supplier.

Specifications

• Memory Size: 256 kilobits (32 kilobytes)
• Interface: Serial Peripheral Interface (SPI)
• Operating Voltage Range: 2.5V to 5.5V
• Operating Temperature Range: -40°C to +85°C
• Write Endurance: 1,000,000 cycles
• Data Retention: 200 years

Pin Configuration

The 25LC256-I/SM has a total of 8 pins, which are assigned specific functions:

1. Chip Select (CS): Used to enable/disable the device for communication.
2. Serial Clock (SCK): Provides the clock signal for synchronous communication.
3. Serial Data Input (SI): Used to input data into the device during write operations.
4. Serial Data Output (SO): Outputs data from the device during read operations.
5. Write Protect (WP): Allows for hardware protection of the memory contents.
6. VCC: Power supply voltage input.
7. Ground (GND): Ground reference for the device.
8. Hold (HOLD): Used to pause serial communication temporarily.

Functional Features

• Byte-level Read and Write Operations: The 25LC256-I/SM allows for individual byte-level read and write operations, providing flexibility in accessing and modifying specific data within the memory.
• Sequential Read Mode: This mode enables continuous reading of multiple bytes without the need for repeated address input, improving efficiency in data retrieval.
• Software Protection: The device supports software-based write protection, allowing users to protect critical data from accidental modification.
• Self-Timed Programming Cycle: The programming cycle is automatically timed by the device, simplifying the write operation process.

Advantages and Disadvantages

Advantages: - Compact size and low power consumption make it suitable for portable devices. - High reliability ensures data integrity over extended periods. - Easy integration with microcontrollers due to the widely used SPI interface. - Wide operating voltage range allows for compatibility with various power supply systems.

Disadvantages: - Limited storage capacity compared to other memory technologies. - Slower write speeds compared to some other non-volatile memory options. - Vulnerable to electrical noise and interference, requiring proper circuit design considerations.

Working Principles

The 25LC256-I/SM utilizes EEPROM technology, which allows for electrically erasing and reprogramming of data. It stores information in a grid of memory cells, with each cell capable of holding one bit of data. The data can be written or read using the SPI interface, which provides a simple and efficient means of communication between the device and a microcontroller.

During write operations, the device applies a high voltage to the memory cell, causing electrons to be trapped in an insulated floating gate. This alters the threshold voltage of the cell, allowing it to store either a "0" or "1" bit. Reading data involves applying a lower voltage to the cell and measuring the resulting current flow, which determines the stored bit value.

Detailed Application Field Plans

The 25LC256-I/SM finds applications in various electronic devices that require non-volatile storage capabilities. Some common application fields include:

1. Consumer Electronics: Used in smart TVs, set-top boxes, and audio/video equipment for storing configuration settings and user preferences.
2. Automotive Systems: Employed in automotive ECUs (Electronic Control Units) for storing calibration data, fault codes, and vehicle-specific settings.
3. Industrial Automation: Integrated into industrial control systems for storing parameter settings, production data, and firmware updates.
4. Medical Devices: Utilized in medical equipment for storing patient data, device configurations, and software updates.
5. Internet of Things (IoT): Incorporated into IoT devices for