Overview
The M27C256B-90B6 is a 256 Kbit EPROM (Erasable Programmable Read-Only Memory) produced by STMicroelectronics. This device is available in two main types: UV (ultra violet erase) and OTP (one time programmable). It is organized as 32,768 by 8 bits, making it suitable for microprocessor systems. The UV version comes in a window ceramic frit-seal package (FDIP28W) that allows for erasure using ultraviolet light, while the OTP version is offered in PDIP28 and PLCC32 packages for applications where content is programmed only once and erasure is not required.
Key Specifications
| Parameter | Description | Value |
|---|---|---|
| Capacity | 256 Kbit (32K x 8 bits) | - |
| Supply Voltage (Read) | 5V ± 10% | - |
| Access Time | 90ns (for M27C256B-90B6) | - |
| Active Current | 30mA at 5MHz | - |
| Standby Current | 100µA | - |
| Programming Voltage | 12.75V ± 0.25V | - |
| Programming Time | 100µs/Word | - |
| Electronic Signature | Manufacturer Code: 20h, Device Code: 8Dh | - |
| Package Types | FDIP28W, PDIP28, PLCC32 | - |
| ECOPACK | Lead-free, compliant with JEDEC Standard JESD97 | - |
Key Features
- Low Power Consumption: Active current of 30mA at 5MHz and standby current of 100µA.
- Two-Line Output Control: Allows for efficient use in larger memory arrays, reducing power dissipation and preventing output bus contention.
- Programming Algorithm: Supports PRESTO II programming algorithm for efficient and reliable programming.
- Electronic Signature: Provides manufacturer and device codes for identification).
- ECOPACK Packages: Available in lead-free packages, compliant with environmental standards).
Applications
The M27C256B-90B6 is ideally suited for microprocessor systems and other applications requiring non-volatile memory. It is particularly useful in:
- Embedded systems where program code or data need to be stored permanently.
- Industrial control systems that require reliable and non-volatile memory.
- Aerospace and automotive applications where the device's robustness and reliability are crucial.
- Any system requiring low power consumption and efficient memory management.
Q & A
- What is the capacity of the M27C256B-90B6 EPROM?
The M27C256B-90B6 has a capacity of 256 Kbit, organized as 32,768 by 8 bits).
- What are the different package types available for the M27C256B?
The device is available in FDIP28W, PDIP28, and PLCC32 packages).
- How is the M27C256B programmed?
The device is programmed by applying a programming voltage of 12.75V ± 0.25V to the VPP pin and using the PRESTO II programming algorithm).
- What is the access time for the M27C256B-90B6?
The access time for the M27C256B-90B6 is 90ns).
- How does the two-line output control function work?
The two-line output control uses Chip Enable (E) and Output Enable (G) to manage data output, ensuring low power dissipation and preventing output bus contention).
- What is the standby current of the M27C256B?
The standby current is 100µA when the device is in standby mode).
- How is the electronic signature of the M27C256B accessed?
The electronic signature is accessed by applying 11.5V to 12.5V on address line A9, with VCC = VPP = 5V, and reading the manufacturer and device codes from the outputs).
- Is the M27C256B available in lead-free packages?
- What is the programming time per word for the M27C256B?
- Can the M27C256B be erased and reprogrammed?
