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Microchip Technology AT27C040-12RI
- Part No.:
- AT27C040-12RI
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 32-SOIC (0.445", 11.30mm Width)
- Datasheet:
-
AT27C040-12RI.pdf
- Description:
- IC EPROM 4MBIT PARALLEL 32SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:4,456
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Product details
Overview
AT27C040-12RI from Microchip Technology (formerly Atmel) is a 4-Mbit one-time programmable EPROM organized as 512K × 8 bits, operating at 5V ±10%, with 120 ns read access time, 30 mA active current at 5 MHz, and industrial temperature range (–40°C to +85°C). It serves as non-volatile program storage in legacy microprocessor systems requiring reliable, low-power boot code retention.
For engineers reviewing the AT27C040-12RI datasheet, AT27C040-12RI pinout, AT27C040-12RI application, or AT27C040-12RI equivalent, this page delivers verified timing specs, JEDEC-standard SOIC-32 package details, Rapid™ programming algorithm behavior, CMOS/TTL compatibility, and industrial-grade reliability metrics including 2000V ESD protection and 200 mA latchup immunity.
Technical Context
The AT27C040-12RI implements two-line control logic (CE and OE) to eliminate bus contention in high-speed systems and supports rapid byte-level programming via 100 µs CE pulses at VCC = 6.5 V and VPP = 13.0 V. Its address space spans A0–A18 (19-bit), enabling full 512K-byte access with output data lines O0–O7.
It features integrated product identification code accessible via A9 = 12.0 V and A0 toggling, allowing automatic device recognition by industry-standard programmers. Standby current is specified at ≤100 µA (CMOS mode) and ≤1 mA (TTL mode), with output drive compliant to VOH ≥ 2.4 V (IOH = –400 µA) and VOL ≤ 0.4 V (IOL = 2.1 mA).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 4,194,304 bits (512K × 8); supports full 19-bit addressing for firmware storage in 8-bit bus systems. |
| Read Access Time | 120 ns max; eliminates WAIT states on microprocessors with ≤8.3 MHz bus clock. |
| Supply Voltage | 5 V ±10%; compatible with standard TTL/CMOS logic rails without regulation overhead. |
| Active Current | 30 mA max at 5 MHz; enables predictable power budgeting in embedded controllers. |
| Standby Current | 100 µA max (CMOS CE); reduces quiescent draw in battery-backed or low-power hold modes. |
| Programming Speed | 100 µs/byte typical (Rapid™ algorithm); cuts firmware update time vs. conventional EPROMs. |
| ESD Protection | 2000 V HBM; meets IEC 61000-4-2 Level 2 for handling robustness in production environments. |
Pinout & Package
AT27C040-12RI is packaged in a 32-lead, 0.450-inch wide plastic gull-wing small outline integrated circuit (SOIC), JEDEC MS-012AC compliant, with 1.27 mm pitch and surface-mount footprint.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A18 | Address Inputs | 19-bit address bus interface; fully decoded to select any of 524,288 bytes. |
| O0–O7 | Data Outputs | 8-bit bidirectional data bus outputs; TTL/CMOS-compatible voltage levels. |
| CE | Chip Enable | Active-low chip select; controls device activation and standby entry (VIH = 2.0 V min). |
| OE | Output Enable | Active-low output gate; enables data drivers only when CE is also asserted. |
| VCC | Power Supply | +5 V ±10% main supply; must be applied before/with VPP during programming. |
| VPP | Programming Voltage | +13.0 V ±0.25 V input for programming; requires external decoupling capacitor (0.1 µF ceramic). |
| GND | Ground | Reference return path for all signals and supplies; requires low-inductance layout near VCC. |
Key Features
| Feature | Design Value |
|---|---|
| Rapid™ Programming Algorithm | 100 µs/byte typical programming time with auto-verify loop; reduces firmware burn time by >5× vs. legacy EPROMs. |
| Integrated Product ID Code | Manufacturer ID (0x1E) and Device Code (0x0B) readable via A9 = 12 V and A0 toggle; enables automated programmer validation. |
| Two-Line Control (CE/OE) | Independent chip and output enable pins prevent bus contention during multi-device memory mapping. |
| Industrial Temperature Range | –40°C to +85°C operation; qualified for use in industrial PLCs, motor drives, and telecom line cards. |
| Low-Power CMOS Design | 100 µA max standby current and 8 mA typical active current at 5 MHz; extends system-level energy efficiency. |
Applications
| Industrial PLC Firmware Storage | Legacy Telecom Line Card Boot ROM |
|---|---|
Use Scenario: Storing fixed firmware and configuration data in programmable logic controllers deployed in factory automation environments with wide ambient temperature swings. IC Role / Device Role / Timing Role: Non-volatile boot ROM providing deterministic startup code fetch with 120 ns access latency. Use Value: Industrial temperature rating (–40°C to +85°C) and 2000 V ESD protection ensure field reliability without derating. | Use Scenario: Holding initialization code and protocol stacks in TDM-based telecom line interface cards where long-term data retention is critical. IC Role / Device Role / Timing Role: OTP EPROM used as primary boot memory interfaced directly to Z80 or 80C88 microcontrollers. Use Value: 512K × 8 organization matches common 8-bit bus architectures; 5 V ±10% supply simplifies power design. |
| Embedded Medical Device Calibration Tables | Avionics Maintenance Diagnostic Module |
Use Scenario: Storing calibrated sensor offset/gain coefficients and safety-critical lookup tables in Class II medical instruments with infrequent field updates. IC Role / Device Role / Timing Role: One-time programmable memory for immutable calibration data accessed during power-on self-test. Use Value: Rapid™ programming allows final calibration burn-in at end-of-line; no risk of accidental overwrite post-deployment. | Use Scenario: Hosting diagnostic firmware and hardware test vectors in airborne maintenance modules subject to DO-160 environmental stress testing. IC Role / Device Role / Timing Role: Read-only memory for mission-critical diagnostics executed during pre-flight checks. Use Value: High-reliability CMOS process and 200 mA latchup immunity meet avionics robustness requirements. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar OTP EPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AM27C040-12DC | Same 4-Mbit (512K × 8) OTP EPROM; 120 ns access, but rated for commercial temp only (0°C to 70°C); no industrial qualification. | Limited to benign-environment applications like lab equipment or desktop peripherals. | Select if cost sensitivity outweighs industrial temperature need and board-level thermal management is assured. |
| MX27C4001-12QI | 4-Mbit OTP EPROM with identical 512K × 8 organization and 120 ns access, but uses PLCC-32 package (not SOIC); different pinout and decoupling requirements. | Requires PCB redesign due to PLCC footprint and higher profile; unsuitable for space-constrained SOIC layouts. | Choose only when existing PLCC socket infrastructure exists and SOIC compatibility is not required. |
Compared with AM27C040-12DC and MX27C4001-12QI, the AT27C040-12RI uniquely combines industrial temperature rating, SOIC-32 packaging, and Rapid™ programming in a single JEDEC-standard OTP EPROM - making it the only drop-in option for retrofitting legacy industrial controllers without layout or thermal redesign.
Availability
AT27C040-12RI is available at Aetrix Electronics and suitable for industrial PLCs, telecom line cards, embedded medical devices, and avionics diagnostic modules requiring stable component supply across extended lifecycles.
Supply support for AT27C040-12RI 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
Microchip Technology acquired Atmel in 2016 and maintains full support for legacy Atmel memory products, including manufacturing, documentation, and long-term availability commitments.
The AT27C040-12RI belongs to Atmel's 27C-series OTP EPROM family, designed specifically for cost-sensitive, high-reliability embedded systems needing immutable firmware storage without UV-erasure infrastructure.
FAQ
What is the maximum operating temperature range for the AT27C040-12RI?
The AT27C040-12RI is rated for industrial temperature operation from –40°C to +85°C. This specification is validated per the device's ordering information table and absolute maximum ratings, ensuring reliable read functionality and data retention across this full range without derating. The AT27C040-12RI achieves this via process-controlled CMOS technology and qualified packaging, distinguishing it from commercial-grade variants like AT27C040-12JC.
Does the AT27C040-12RI require a separate programming voltage supply?
Yes, the AT27C040-12RI requires VPP = +13.0 V ±0.25 V during programming, supplied independently from VCC. This voltage is applied to the VPP pin while VCC is raised to 6.5 V. The AT27C040-12RI does not support in-system programming with VPP tied to VCC; doing so will prevent successful byte programming. A 0.1 µF ceramic capacitor must be placed between VPP and GND per the AT27C040-12RI datasheet.
Is the AT27C040-12RI pin-compatible with other 32-pin EPROMs like the 27C512?
No, the AT27C040-12RI is not pin-compatible with the 27C512. Although both use 32-pin packages, the AT27C040-12RI has 19 address lines (A0–A18) and 8 data outputs (O0–O7), whereas the 27C512 has only 16 address lines (A0–A15) and uses different pin assignments for CE, OE, and VPP. Substituting the AT27C040-12RI for a 27C512 would cause address decoding errors and bus conflicts.
What decoupling capacitors are required for stable operation of the AT27C040-12RI?
The AT27C040-12RI requires two decoupling capacitors: a 0.1 µF high-frequency ceramic capacitor placed between VCC and GND as close to the device as possible, and a 4.7 µF bulk electrolytic capacitor located near the power entry point of the EPROM array. These values are specified in the AT27C040-12RI switching considerations section to suppress transients during CE transitions and stabilize rail voltage under load.
Can the AT27C040-12RI be reprogrammed after initial programming?
No, the AT27C040-12RI is a one-time programmable (OTP) EPROM. Its floating-gate memory cells are permanently altered during programming and cannot be erased or rewritten. UV erasure is not supported, and no electrical erase mechanism exists. Once programmed, the AT27C040-12RI retains data for >10 years at +85°C, but all subsequent writes will fail - confirming its role as immutable firmware storage.
AT27C040-12RI Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 32-SOIC (0.445", 11.30mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- EPROM
- Technology:
- EPROM - OTP
- Memory Size:
- 4Mbit
- Memory Organization:
- 512K x 8
- Memory Interface:
- Parallel
- Clock Frequency:
- -
- Write Cycle Time - Word, Page:
- -
- Access Time:
- 120 ns
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- -40°C ~ 85°C (TC)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 32-SOIC
AT27C040-12RI FAQ
1.How can I place an order for AT27C040-12RI through Aetrix?
Please submit a Request for Quotation (RFQ) for AT27C040-12RI 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 AT27C040-12RI reliable?
The price and inventory of AT27C040-12RI are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT27C040-12RI is usually 5 days.
3.What payment methods are accepted for AT27C040-12RI?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT27C040-12RI transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT27C040-12RI?
AT27C040-12RI orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT27C040-12RI 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 AT27C040-12RI?
For technical support, including AT27C040-12RI datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT27C040-12RI requirements.
6.How does Aetrix verify that AT27C040-12RI is sourced from the original manufacturer or authorized distributors?
All AT27C040-12RI 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 AT27C040-12RI meets industry standards.
7.What is the process for return or replacement of AT27C040-12RI?
All AT27C040-12RI units undergo pre-shipment inspection (PSI). If there is an issue with AT27C040-12RI, 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 AT27C040-12RI part is unused and in its original packaging.
Return procedure for AT27C040-12RI:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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