The AT27C020 is a low-power, high-performance, 2,097,152-bit, one-time programmable read-only memory (OTP EPROM) organized as 256K by 8 bits. It requires only one 5V power supply in normal read mode operation. Any byte can be accessed in less than 55 ns, eliminating the need for speed-reducing WAIT states on high-performance microprocessor systems. In read mode, the AT27C020 typically consumes 8 mA. Standby mode supply current is typically less than 10 µA. The AT27C020 is available in a choice of industry-standard JEDEC-approved one-time programmable (OTP) plastic PDIP, PLCC and TSOP packages. All devices feature two-line control (CE, OE) to give designers the flexibility to prevent bus contention. With 256K bytes storage capability, the AT27C020 allows firmware to be stored reliably and to be accessed by the system without the delays of mass storage media. Atmel’s AT27C020 has additional features to ensure high quality and efficient production.
The AT27C020 is a 2‑megabit one‑time programmable EPROM organized as 256 K × 8 bits. It operates from a single 5 V supply and provides fast 55 ns read access without requiring wait states. The device is offered in standard 32‑lead PDIP, PLCC and TSOP packages and includes features such as 2 kV ESD protection, 200 mA latch‑up immunity, and a rapid programming algorithm of 100 ps per byte.
Electrical characteristics include low‑power standby current, a 25 mA active current at 5 MHz, and operation over industrial temperature ranges (‑55 °C to +125 °C). The datasheet also details pin configurations, timing diagrams for read and program operations, and package dimensions.
| Read Access Time | 55 ns |
|---|---|
| Standby Current | 100 pA max |
| Active Current (5 MHz) | 25 mA |
| Supply Voltage | 5 V ±10% |
| ESD Protection | 2 kV |
| Latch‑up Immunity | 200 mA |
| Programming Speed | 100 ps/byte (typical) |
| Storage Temperature | -65 °C to +150 °C |
| Package Options | 32‑lead PDIP, PLCC, TSOP |
The device provides a read access time of 55 ns.
It operates from a 5 V supply with a tolerance of ±10 %.
Standby current is limited to a maximum of 100 pA.