Overview
The M27C256B-70XF1 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 EPROM is offered in various packages, including FDIP28W (window ceramic frit-seal package), PDIP28, and PLCC32, with the FDIP28W allowing for UV erasure through its transparent lid.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Memory Size | 256 Kbit (32Kb × 8) | |
| Supply Voltage (Read Operation) | 5V ± 10% | V |
| Access Time | 45ns | ns |
| Active Current | 30mA at 5MHz | mA |
| Standby Current | 100µA | µA |
| Programming Voltage | 12.75V ± 0.25V | V |
| Programming Time | 100µs/Word | µs |
| Manufacturer Code | 20h | |
| Device Code | 8Dh | |
| Packages | FDIP28W, PDIP28, PLCC32 |
Key Features
- Low Power Consumption: Active current of 30mA at 5MHz and standby current of 100µA.
- Programming and Erasure: Programmable with a voltage of 12.75V ± 0.25V and erasable using UV light for UV EPROM versions.
- Electronic Signature: Provides manufacturer and device codes for identification.
- ECOPACK® Packages: Available in lead-free packages to meet environmental requirements.
- Two-Line Output Control: Features chip enable (E) and output enable (G) for efficient memory array management.
Applications
The M27C256B-70XF1 is ideally suited for microprocessor systems, particularly in applications where non-volatile memory is required. It can be used in various embedded systems, industrial control systems, and other electronic devices that need programmable memory. The OTP version is suitable for applications where the content is programmed only once and erasure is not required.
Q & A
- What is the memory size of the M27C256B-70XF1?
The memory size is 256 Kbit, organized as 32,768 by 8 bits.
- What are the different package types available for the M27C256B-70XF1?
The device is available in FDIP28W, PDIP28, and PLCC32 packages.
- What is the supply voltage for read operations?
The supply voltage for read operations is 5V ± 10%.
- What is the access time of the M27C256B-70XF1?
The access time is 45ns.
- How does the standby mode reduce power consumption?
In standby mode, the supply current is reduced from 30mA to 100µA by applying a CMOS high signal to the E input.
- What is the programming voltage and time for the M27C256B-70XF1?
The programming voltage is 12.75V ± 0.25V, and the programming time is 100µs per word.
- How does the electronic signature feature work?
The electronic signature mode is activated by forcing 11.5V to 12.5V on address line A9, allowing the manufacturer and device codes to be read out.
- What is the purpose of the two-line output control feature?
The two-line output control feature allows for efficient management of memory arrays by using chip enable (E) and output enable (G) to minimize power dissipation and prevent output bus contention.
- Are the packages of the M27C256B-70XF1 environmentally friendly?
- What are the typical applications of the M27C256B-70XF1?
