AT27C256R-90JC

Product Overview

Category

AT27C256R-90JC belongs to the category of programmable read-only memory (PROM) chips.

Use

This product is commonly used for storing data that needs to be permanently stored and cannot be modified. It is widely utilized in various electronic devices such as computers, microcontrollers, and embedded systems.

Characteristics

• Non-volatile: The stored data remains intact even when power is turned off.
• High storage capacity: The AT27C256R-90JC has a capacity of 256 kilobits (32 kilobytes).
• Fast access time: With a speed of 90 nanoseconds, it provides quick retrieval of stored information.
• Low power consumption: This chip operates efficiently with low power requirements.

Package

The AT27C256R-90JC is available in a 32-pin PLCC (Plastic Leaded Chip Carrier) package. This package offers protection to the integrated circuit and facilitates easy installation on printed circuit boards.

Essence

The essence of this product lies in its ability to store data permanently, making it ideal for applications where data integrity is crucial.

Packaging/Quantity

The AT27C256R-90JC is typically packaged in reels or tubes, containing multiple units per package. The exact quantity may vary depending on the supplier.

Specifications

• Memory Capacity: 256 kilobits (32 kilobytes)
• Access Time: 90 nanoseconds
• Supply Voltage: 5 volts
• Operating Temperature Range: -40°C to +85°C
• Package Type: 32-pin PLCC

Detailed Pin Configuration

1. A14
2. A12
3. A7
4. A6
5. A5
6. A4
7. A3
8. A2
9. A1
10. A0
11. /OE (Output Enable)
12. /CE (Chip Enable)
13. NC (No Connection)
14. D7
15. D6
16. D5
17. D4
18. D3
19. D2
20. D1
21. D0
22. VCC (Power Supply)
23. GND (Ground)
24. A8
25. A9
26. A11
27. A10
28. /WE (Write Enable)
29. /PGM (Program)
30. /BYTE (Byte/Word Organization)
31. /ACC (Access Time Control)
32. /WP (Write Protect)

Functional Features

• Non-volatile storage: The AT27C256R-90JC retains data even when power is disconnected.
• High-speed access: With an access time of 90 nanoseconds, it provides quick retrieval of stored information.
• Easy integration: The chip can be easily integrated into various electronic systems due to its standard pin configuration and package.

Advantages and Disadvantages

Advantages

• Permanent data storage ensures data integrity.
• Fast access time allows for efficient retrieval of information.
• Low power consumption contributes to energy efficiency.
• Easy integration into existing electronic systems.

Disadvantages

• Data cannot be modified once programmed.
• Limited storage capacity compared to other memory technologies.
• Relatively higher cost per unit compared to some alternative memory solutions.

Working Principles

The AT27C256R-90JC operates based on the principle of electrical charge trapping in a floating gate structure. During programming, a high voltage is applied to the control gates, allowing electrons to tunnel through a thin oxide layer and become trapped in the floating gate. This trapped charge alters the threshold voltage of the memory cell, representing either a "0" or a "1". During read operations, the stored charge is sensed to determine the stored data.

Detailed Application Field Plans

The AT27C256R-90JC finds applications in various fields, including: 1. Computer systems: Used for storing firmware, BIOS, and other critical system data. 2. Microcontrollers: Provides non-volatile memory for program storage. 3. Embedded systems: Used for storing configuration data, calibration values, and lookup tables. 4. Automotive electronics: Utilized for storing critical data in engine control units (ECUs) and other automotive systems.

Detailed and Complete Alternative Models

1. AT28C256-15PU: Similar capacity and functionality with a different package type (DIP).
2. AM29F040B-90JC: Flash memory alternative with higher capacity and faster access time.
3. M27C256B-12F1: EPROM alternative with similar capacity and slower access time.

These alternative models offer similar functionalities but may differ in terms of package type, capacity, access time, and cost.

In conclusion, the AT27C256R-90JC is a programmable