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Microchip Technology AT27C512R-45PI
- Part No.:
- AT27C512R-45PI
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 28-DIP (0.600", 15.24mm)
- Datasheet:
-
AT27C512R-45PI.pdf
- Description:
- IC EPROM 512KBIT PARALLEL 28DIP
- Quantity:
- Payment:
- Shipping:
Inventory:1,318
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Product details
Overview
AT27C512R-45PI from Atmel is a 512 Kbit (64K × 8) one-time programmable EPROM with 45 ns read access time, 5V ±10% supply operation, and industrial temperature range (–40°C to +85°C). It features CMOS/TTL-compatible I/O, dual-line control (CE/OE), and rapid programming at 100 µs/byte - enabling high-speed firmware storage in microprocessor-based embedded systems without wait states.
For engineers reviewing the AT27C512R-45PI datasheet, AT27C512R-45PI pinout, AT27C512R-45PI application, or AT27C512R-45PI equivalent, key selection considerations include its OTP architecture, JEDEC-standard 28-lead PDIP package, 100 µA max standby current, and compatibility with legacy 5V bus systems requiring non-volatile code storage.
Technical Context
The AT27C512R-45PI implements a parallel-addressed OTP EPROM architecture with 16-bit address inputs (A0–A15), 8-bit bidirectional data outputs (O0–O7), and two active-low control lines: Chip Enable (CE) and Output Enable/VPP (OE/VPP). Its Rapid™ programming algorithm uses 13.0 V on OE/VPP and 6.5 V on VCC for byte-level programming with verification loops.
It supports three operating modes: Read (CE=OE=VIL), Standby (CE=VIH), and Rapid Program (CE=VIL, OE/VPP=VPP). The device integrates product identification logic where A9 is driven to 12.0 V to select manufacturer/device codes, and includes ESD protection (2,000 V) and latchup immunity (200 mA).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 512 Kbit (64K × 8) - provides sufficient space for boot code or firmware in 8-bit microcontroller systems. |
| Read Access Time | 45 ns - eliminates WAIT states on 5 MHz Z80, 8051, or 68K-based systems. |
| Supply Voltage | 5 V ±10% - compatible with standard TTL/CMOS logic rails without regulation overhead. |
| Standby Current | 100 µA max - enables low-power retention in battery-backed or intermittent-operation designs. |
| Active Current | 20 mA max at 5 MHz - supports sustained read bursts without thermal derating in industrial enclosures. |
| Programming Voltage | VPP = 13.0 V ±0.25 V - requires dedicated programming hardware; not compatible with standard 5V-only programmers. |
| Operating Temperature | –40°C to +85°C - qualified for industrial control, motor drives, and factory automation equipment. |
Pinout & Package
AT27C512R-45PI is supplied in a 28-lead, 0.600-inch wide plastic dual inline package (PDIP), per JEDEC MS-011 AB. Pin 1 is index-marked; pins are spaced 0.100 inch (2.54 mm) apart with 0.300 inch row spacing.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A15 | Address Inputs | 16-bit parallel address bus; latched on CE falling edge for memory location selection. |
| O0–O7 | Data Outputs | 8-bit tristate data bus; driven only when CE=OE=VIL; high-impedance otherwise. |
| CE | Chip Enable | Active-low global enable; disables outputs and reduces current to 100 µA when high. |
| OE/VPP | Output Enable / Programming Voltage | Active-low output gate during read; supplies 13 V programming voltage during write mode. |
| GND | Ground Reference | Signal and power return; requires local 0.1 µF ceramic decoupling per device. |
| VCC | Power Supply | 5 V ±10% main supply; must be applied simultaneously with or before OE/VPP. |
Key Features
| Feature | Design Value |
|---|---|
| Rapid™ Programming Algorithm | 100 µs/byte typical programming time with automatic verification/retry - reduces production programming cycle time by >5× vs. legacy EPROMs. |
| Integrated Product Identification Code | Manufacturer ID (0x1E) and Device Code (0x0D) readable via A9=12 V and A0 toggle - enables automated programmer validation and BOM traceability. |
| Two-Line Control Architecture | Independent CE and OE inputs - prevents bus contention in shared-memory systems and simplifies timing design vs. single-control alternatives. |
| High-Reliability Process | 2,000 V HBM ESD rating and 200 mA latchup immunity - ensures robustness in manufacturing handling and noisy industrial environments. |
| JEDEC-Standard Packaging | 28P6 PDIP footprint - allows drop-in replacement of legacy 27C512 variants and compatibility with standard socketing and wave-solder tooling. |
Applications
| Industrial PLC Firmware Storage | Legacy Microcontroller Boot ROM |
|---|---|
Use Scenario: Storing fixed ladder logic and I/O mapping tables in programmable logic controllers deployed in factory floors with ambient temperatures up to 85°C. IC Role / Device Role / Timing Role: Non-volatile boot memory providing deterministic 45 ns instruction fetch timing to 80C31 or 80C186 derivatives. Use Value: Eliminates reliance on external EEPROM or Flash with slower write cycles; retains firmware integrity across power loss without backup capacitors. |
Use Scenario: Hosting startup code and interrupt vectors for 8-bit microcontrollers in medical diagnostic instruments requiring long-term data retention and regulatory compliance. IC Role / Device Role / Timing Role: OTP EPROM acting as primary program memory with direct address/data bus interface and no runtime configuration overhead. Use Value: Guarantees unalterable firmware execution path; avoids security risks associated with field-upgradable memory in Class IIa devices. |
| Automotive Engine Control Module (ECM) | Point-of-Sale Terminal BIOS |
Use Scenario: Holding calibration maps and safety-critical engine timing parameters in automotive ECMs operating across –40°C to +125°C (using -45PA variant); this part's -45PI serves as industrial-grade reference. IC Role / Device Role / Timing Role: Read-only firmware repository accessed synchronously by 16-bit MCUs during cold start sequences. Use Value: Delivers sub-50 ns access latency required for real-time fuel injection timing - faster than most 5V Flash alternatives at equivalent density. |
Use Scenario: Storing secure boot firmware and cryptographic keys in retail POS terminals subject to frequent power cycling and physical tampering attempts. IC Role / Device Role / Timing Role: Immutable code storage element interfaced to 8088/80286-derived controllers via ISA bus. Use Value: Prevents unauthorized firmware modification; OTP architecture ensures zero risk of accidental overwrites during field service or voltage transients. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar OTP EPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AM27C512-45DC | Same 64K×8 OTP EPROM, 45 ns access, but uses AMD's process; higher 25 mA active current and no integrated ID code. | Requires external programmer ID verification; less suitable for automated high-volume programming lines. | Select when cost sensitivity outweighs programming efficiency and traceability requirements. |
| MX27C512-45PC | Macronix OTP EPROM with identical pinout and timing, but 150 µA max standby current and no Rapid™ algorithm support. | Lacks 100 µs/byte programming; average programming time ~500 µs/byte - increases production throughput time. | Choose only if existing inventory or legacy tooling mandates Macronix-specific programming voltage profiles. |
Compared with AM27C512-45DC and MX27C512-45PC, the AT27C512R-45PI delivers lower standby power, faster verified programming, and built-in electronic identification - making it optimal for new industrial designs prioritizing production yield, firmware traceability, and thermal margin.
Availability
AT27C512R-45PI is available at Aetrix Electronics and suitable for industrial control systems, legacy microcontroller upgrades, and embedded firmware storage applications requiring stable component supply, long-lifecycle assurance, and JEDEC-standard packaging.
Supply support for AT27C512R-45PI includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Atmel Corporation was a U.S.-based semiconductor company specializing in microcontrollers, non-volatile memory, and analog products before its acquisition by Microchip Technology in 2016. Its legacy memory portfolio emphasized reliability and industrial qualification.
The AT27C512R belongs to Atmel's OTP EPROM family designed for firmware storage in resource-constrained, high-reliability embedded systems where code immutability, 5V compatibility, and fast read performance are critical.
FAQ
What is the maximum programming voltage required for AT27C512R-45PI?
The AT27C512R-45PI requires OE/VPP = 13.0 V ±0.25 V during programming, with VCC raised to 6.5 V ±0.25 V. This dual-voltage requirement is mandatory for reliable byte programming and cannot be substituted with 5 V alone. The AT27C512R-45PI datasheet specifies VID on A9 must also reach 11.5–12.5 V for product identification reads.
Is AT27C512R-45PI pin-compatible with older 27C512 variants?
Yes, the AT27C512R-45PI maintains full pin-to-pin compatibility with industry-standard 27C512 EPROMs in 28-lead PDIP packages, including identical A0–A15, O0–O7, CE, OE/VPP, VCC, and GND assignments. Its PDIP footprint matches JEDEC MS-011 AB, enabling direct replacement in existing sockets and PCB layouts.
Does AT27C512R-45PI support read operations at 5 MHz bus speed?
Yes, the AT27C512R-45PI supports continuous read operations at 5 MHz with ICC ≤ 20 mA, meeting AC timing specifications including tACC ≤ 45 ns and tOE ≤ 20 ns. Its 5V ±10% supply and TTL/CMOS-compatible I/O ensure clean signal integrity on standard 5 MHz microprocessor buses without additional level-shifting.
What is the purpose of the NC pins on AT27C512R-45PI?
The AT27C512R-45PI has no NC (No Connect) pins in its 28-lead PDIP package - all 28 pins are assigned functions per the datasheet: A0–A15 (16), O0–O7 (8), CE, OE/VPP, VCC, and GND. NC pins appear only in PLCC (pins 1 and 17) and TSOP variants, not in the PDIP version used for AT27C512R-45PI.
Can AT27C512R-45PI be reprogrammed after initial programming?
No, the AT27C512R-45PI is a one-time programmable (OTP) EPROM. Once a memory cell is programmed (fused), it cannot be erased or rewritten. Programming is irreversible; the device is intended for final firmware images where code stability and security are mandatory, not for development iteration.
AT27C512R-45PI Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 28-DIP (0.600", 15.24mm)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- EPROM
- Technology:
- EPROM - OTP
- Memory Size:
- 512Kbit
- Memory Organization:
- 64K x 8
- Memory Interface:
- Parallel
- Clock Frequency:
- -
- Write Cycle Time - Word, Page:
- -
- Access Time:
- 45 ns
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- -40°C ~ 85°C (TC)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 28-PDIP
AT27C512R-45PI FAQ
1.How can I place an order for AT27C512R-45PI through Aetrix?
Please submit a Request for Quotation (RFQ) for AT27C512R-45PI on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for AT27C512R-45PI reliable?
The price and inventory of AT27C512R-45PI are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT27C512R-45PI is usually 5 days.
3.What payment methods are accepted for AT27C512R-45PI?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT27C512R-45PI transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT27C512R-45PI?
AT27C512R-45PI orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT27C512R-45PI order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for AT27C512R-45PI?
For technical support, including AT27C512R-45PI datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT27C512R-45PI requirements.
6.How does Aetrix verify that AT27C512R-45PI is sourced from the original manufacturer or authorized distributors?
All AT27C512R-45PI products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that AT27C512R-45PI meets industry standards.
7.What is the process for return or replacement of AT27C512R-45PI?
All AT27C512R-45PI units undergo pre-shipment inspection (PSI). If there is an issue with AT27C512R-45PI, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The AT27C512R-45PI part is unused and in its original packaging.
Return procedure for AT27C512R-45PI:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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