AT27C256R: Top Choice in United States (USA) Utsource Holding Company Limited

Description

Parameter	Symbol	Conditions	Min	Typ	Max	Unit
Supply Voltage	VCC	Operating	2.7		5.5	V
Standby Current	ICC	VCC = 5.5V, All pins Hi-Z		1		μA
Active Current	ICC	Reading		30		mA
Output High Level Voltage	VOH	IO ≤ -1mA	2.4		VCC	V
Output Low Level Voltage	VOL	IO ≥ 1mA			0.5	V
Access Time	tACC	VCC = 5.5V		90		ns
Data Retention Time				20		Years

Power Supply Connection:
- Connect the VCC pin to a power supply within the operating voltage range (2.7V to 5.5V).
- Ensure that the GND pin is connected to ground.
Address and Data Lines:
- Connect address lines A0-A17 to the appropriate address bus.
- Connect data lines D0-D7 to the data bus for read/write operations.
Chip Enable (CE):
- CE must be low for the chip to be active. When high, the device enters standby mode.
Output Enable (OE):
- OE must be low during read operations. It enables the outputs when low.
Write Protect (WP):
- The WP pin can be used to prevent accidental writes. Connect it to VCC to enable write protection or to GND to allow writing.
Reading Data:
- To read data, set CE and OE low and provide the desired address on the address lines. Data will appear on the data lines after the access time (tACC).
Writing Data:
- Writing is not directly supported by this ROM. For programming, use an external programmer designed for the AT27C256R.
Handling:
- Handle with care as ESD (Electrostatic Discharge) can damage the device. Use proper anti-static precautions.
Storage:
- Store in a dry environment to avoid moisture damage. Keep away from strong magnetic fields.
End of Life:
- After approximately 20 years, data retention may degrade. Plan for replacement if long-term storage is required.

(For reference only)