Overview
The M27C256B-70C1 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 M27C256B is offered in various packages, including FDIP28W (window ceramic frit-seal package), PDIP28, and PLCC32, with the FDIP28W allowing for UV erasure and the others being one-time programmable. The device is also available in ECOPACK® packages, which are lead-free and comply with environmental standards.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Capacity | 256 Kbit (32Kb × 8) | |
| Supply Voltage (Read Operation) | 5V ± 10% | V |
| Access Time | 70ns (for -70C1 speed grade) | ns |
| Active Current | 30mA at 5MHz | mA |
| Standby Current | 100µA | µA |
| Programming Voltage | 12.75V ± 0.25V | V |
| Programming Time | 100µs/Word | µs |
| Ambient Operating Temperature | –40 to 125°C | °C |
| Manufacturer Code | 20h | |
| Device Code | 8Dh |
Key Features
- Low Power Consumption: Active current of 30mA at 5MHz and standby current of 100µA.
- Fast Access Time: 70ns for the -70C1 speed grade.
- Programming Flexibility: Supports both UV erasable and one-time programmable options.
- Electronic Signature: Allows for the reading of a binary code to identify the manufacturer and device type.
- Two-Line Output Control: Features chip enable (E) and output enable (G) for efficient memory array management.
- ECOPACK® Packages: Lead-free packages that meet environmental standards.
Applications
The M27C256B-70C1 is ideally suited for microprocessor systems and other applications requiring non-volatile memory. It is commonly used in:
- Embedded systems requiring program storage.
- Industrial control systems.
- Automotive electronics.
- Consumer electronics where firmware storage is needed.
Q & A
- What is the capacity of the M27C256B-70C1?
The M27C256B-70C1 has a capacity of 256 Kbit, organized as 32,768 by 8 bits.
- What are the different package options available for the M27C256B?
The device is available in FDIP28W, PDIP28, and PLCC32 packages.
- What is the access time for the M27C256B-70C1?
The access time for the -70C1 speed grade is 70ns.
- How does the two-line output control function work?
The two-line output control uses chip enable (E) and output enable (G) to manage memory arrays efficiently, ensuring low power dissipation and preventing output bus contention.
- What is the purpose of the Electronic Signature mode?
The Electronic Signature mode allows the reading of a binary code to identify the manufacturer and device type, useful for programming equipment to match the device with its corresponding programming algorithm.
- What are the programming voltage and time for the M27C256B?
The programming voltage is 12.75V ± 0.25V, and the programming time is 100µs per word.
- 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 are the environmental benefits of ECOPACK® packages?
ECOPACK® packages are lead-free and comply with environmental standards, making them more environmentally friendly.
- What is the ambient operating temperature range for the M27C256B-70C1?
The ambient operating temperature range is –40 to 125°C.
- How can multiple M27C256Bs be programmed in parallel?
Multiple devices can be programmed in parallel by ensuring that all like inputs, except E, are common. A TTL low level pulse applied to a device's E input with VPP at 12.75V will program that device while inhibiting others.
