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Microchip Technology AT27C040-70PC
- Part No.:
- AT27C040-70PC
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 32-DIP (0.600", 15.24mm)
- Datasheet:
-
AT27C040-70PC.pdf
- Description:
- IC EPROM 4MBIT PARALLEL 32DIP
- Quantity:
- Payment:
- Shipping:
Inventory:3,107
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Product details
Overview
AT27C040-70PC from Atmel is a 4-Mbit (512K × 8) one-time programmable EPROM with 70 ns read access time, 5V ±10% single-supply operation, and JEDEC-standard 32-lead PDIP packaging. It delivers CMOS/TTL-compatible I/O, 100 µA max standby current, and supports high-speed microprocessor systems without WAIT states.
For engineers reviewing the AT27C040-70PC datasheet, AT27C040-70PC pinout, AT27C040-70PC application, or AT27C040-70PC equivalent, key selection criteria include verified 70 ns tACC timing, VPP = 12.0 V programming voltage, industrial-grade temperature range support, and compatibility with standard EPROM programmers using Rapid™ algorithm.
Technical Context
The AT27C040-70PC implements a two-line control architecture (CE and OE) to prevent bus contention in high-speed systems. Its address space spans A0–A18 (19-bit), enabling full 512K-byte decoding with integrated product identification code accessible via A9 = 12.0 V and A0 toggling.
It uses Atmel's scaled CMOS process for low-power operation: 30 mA active current at 5 MHz and ≤100 µA standby. Programming requires VCC = 6.5 V and VPP = 13.0 V, with a 100 µs CE pulse width and up to 10 reprogramming attempts per byte during verification.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 4,194,304 bits (512K × 8) - supports firmware storage for 8-bit microcontrollers and boot ROM applications |
| Read Access Time | 70 ns max - enables direct interface with 14 MHz+ CPUs without wait-state insertion |
| Supply Voltage | 5V ±10% - compatible with standard TTL/CMOS logic rails and legacy embedded power domains |
| Standby Current | 100 µA max - ensures ultra-low quiescent power in battery-backed or energy-sensitive systems |
| Programming Voltage | VPP = 12.0 ±0.5 V - requires dedicated programming supply; not compatible with 5V-only programmers |
| Operating Temp | 0°C to +70°C - commercial-grade rating suitable for office, lab, and non-automotive industrial environments |
| ESD Protection | 2000V HBM - enhances handling robustness during manual PCB assembly and rework |
Pinout & Package
AT27C040-70PC is supplied in a 32-lead, 0.600" wide plastic dual inline package (PDIP), JEDEC MS-001 compliant, with 0.100" lead pitch and through-hole mounting.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A18 | Address Inputs | 19-bit address bus supporting full 512K-byte memory map; A0 is LSB |
| O0–O7 | Data Outputs | 8-bit bidirectional data bus (output only); TTL/CMOS compatible drive levels |
| CE | Chip Enable | Active-low chip select; controls device activation and rapid programming mode entry |
| OE | Output Enable | Active-low output gate; enables data bus drivers independently of CE for bus sharing |
| VPP | Programming Voltage | 12.0 V input required only during programming; must be applied after VCC and removed before VCC |
| VCC | Power Supply | +5V ±10% main supply; powers logic and outputs during read; supplies internal charge pump during programming |
| GND | Ground Reference | Signal and power return; requires local 0.1 µF ceramic decoupling per device |
Key Features
| Feature | Design Value |
|---|---|
| Rapid™ Programming Algorithm | 100 µs/byte typical programming time with automatic verify-and-reprogram loop per byte |
| Integrated Product ID Code | Manufacturer ID (0x1E) and Device Code (0x0B) readable via A9 = 12.0 V and A0 toggle |
| Two-Line Control Architecture | Independent CE and OE pins eliminate bus contention and enable flexible memory mapping |
| High-Reliability CMOS Process | 200 mA latchup immunity and 2000V ESD protection ensure robust operation in noisy environments |
| JEDEC-Standard Packaging | PDIP, PLCC, and TSOP variants share identical pinout and timing - simplifies footprint migration |
Applications
| Industrial PLC Firmware Storage | Legacy Microcontroller Boot ROM |
|---|---|
Use Scenario: Storing fixed ladder logic and I/O configuration in programmable logic controllers deployed in factory automation cabinets. IC Role / Device Role / Timing Role: Non-volatile boot memory providing deterministic 70 ns instruction fetch timing for real-time scan cycles. Use Value: Eliminates need for external wait-state generators and ensures consistent startup behavior across temperature and voltage variations. |
Use Scenario: Holding initialization code and interrupt vectors for Z80, 8051, or 68000-based embedded controllers in test equipment and instrumentation. IC Role / Device Role / Timing Role: Primary read-only program memory mapped into CPU address space with A0–A18 decoded directly. Use Value: Enables zero-wait-state execution at 14 MHz CPU clock, reducing system latency and simplifying timing budget allocation. |
| Medical Device Calibration Data | Avionics System Configuration ROM |
Use Scenario: Storing factory-calibrated sensor coefficients and safety-critical lookup tables in Class II medical analyzers. IC Role / Device Role / Timing Role: Tamper-resistant OTP storage accessed during power-on self-test (POST) before runtime software initialization. Use Value: Guarantees data integrity over 20+ year service life with no risk of accidental overwrite or bit corruption. |
Use Scenario: Holding flight control parameter sets and hardware revision identifiers in certified airborne electronics modules. IC Role / Device Role / Timing Role: Read-only configuration memory validated during Built-In Test (BIT) prior to aircraft power-up sequence. Use Value: Meets DO-254 Level A traceability requirements via manufacturer ID and device code verification during production test. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar OTP EPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AM27C040-70DC | Same 4-Mbit size and 70 ns speed, but AMD-manufactured; requires VPP = 12.5 V, slightly higher ICC active current (35 mA) | Identical pinout and timing; differs in programming voltage tolerance and ID code format | Select when sourcing from AMD-qualified supply chains or where cross-programmer compatibility with AMD tools is required |
| MX27C4001-70PC | Macronix variant with identical 512K × 8 organization and PDIP-32 package; tACC = 70 ns, but VPP = 12.5 V and standby current = 200 µA | Same physical footprint and read interface; lacks integrated product ID code and Rapid™ algorithm support | Choose for cost-sensitive designs where ID code verification and fast programming are not required |
Compared with AM27C040-70DC and MX27C4001-70PC, the AT27C040-70PC offers tighter standby current (100 µA vs. 200 µA), guaranteed Rapid™ programming compatibility, and on-chip manufacturer/device ID - critical for automated programming validation and long-term BOM traceability.
Availability
AT27C040-70PC is available at Aetrix Electronics and suitable for industrial PLC firmware storage, legacy microcontroller boot ROM, and medical device calibration data applications requiring stable component supply and long-lifecycle support.
Supply support for AT27C040-70PC 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.
The AT27C040-70PC belongs to Atmel's OTP EPROM product line, designed specifically for cost-effective, high-reliability firmware and configuration storage in legacy and maintenance-critical embedded systems.
FAQ
What is the maximum operating frequency supported by the AT27C040-70PC?
The AT27C040-70PC does not operate at a clock frequency itself, but its 70 ns access time supports CPU bus frequencies up to approximately 14 MHz in zero-wait-state configurations. This is derived from tACC ≤ 70 ns, allowing full address-to-data propagation within one CPU cycle at that rate. The AT27C040-70PC remains stable under these conditions across its 0°C to +70°C commercial temperature range.
Can the AT27C040-70PC be reprogrammed after initial programming?
No, the AT27C040-70PC is a one-time programmable (OTP) EPROM. Once programmed, its memory cells cannot be erased or rewritten. UV erasure is not supported - unlike UV-erasable EPROMs - and no electrical erase mechanism exists. The AT27C040-70PC is intended for final firmware images or immutable configuration data where field updates are unnecessary.
What is the purpose of the VPP pin on the AT27C040-70PC?
The VPP pin on the AT27C040-70PC supplies +12.0 V ±0.5 V exclusively during programming operations to enable Fowler-Nordheim tunneling into the floating gate. It must be applied after VCC and removed before VCC to prevent latchup. During normal read mode, VPP is tied to VCC or left unconnected per design; incorrect VPP sequencing will damage the AT27C040-70PC or cause programming failure.
Does the AT27C040-70PC support both CMOS and TTL logic families?
Yes, the AT27C040-70PC features CMOS and TTL compatible inputs and outputs. Input thresholds meet VIH ≥ 2.0 V and VIL ≤ 0.8 V, while output drive meets VOH ≥ 2.4 V at –400 µA and VOL ≤ 0.4 V at 2.1 mA - satisfying both TTL and CMOS loading requirements. This allows direct interfacing with 8051, Z80, and 68000 family microcontrollers without level-shifting circuitry.
How is the Integrated Product Identification Code accessed on the AT27C040-70PC?
The Integrated Product Identification Code on the AT27C040-70PC is accessed by setting A9 to 12.0 V (VID = 11.5–12.5 V), holding A1–A18 low, and toggling A0: low selects the Manufacturer ID (0x1E), high selects the Device Code (0x0B). Both bytes appear on O7–O0 during read mode with CE and OE asserted. This feature enables automated programmer validation of the AT27C040-70PC before programming begins.
AT27C040-70PC Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 32-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:
- 4Mbit
- Memory Organization:
- 512K x 8
- Memory Interface:
- Parallel
- Clock Frequency:
- -
- Write Cycle Time - Word, Page:
- -
- Access Time:
- 70 ns
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- 0°C ~ 70°C (TC)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 32-PDIP
AT27C040-70PC FAQ
1.How can I place an order for AT27C040-70PC through Aetrix?
Please submit a Request for Quotation (RFQ) for AT27C040-70PC 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 AT27C040-70PC reliable?
The price and inventory of AT27C040-70PC are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT27C040-70PC is usually 5 days.
3.What payment methods are accepted for AT27C040-70PC?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT27C040-70PC transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT27C040-70PC?
AT27C040-70PC orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT27C040-70PC 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 AT27C040-70PC?
For technical support, including AT27C040-70PC datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT27C040-70PC requirements.
6.How does Aetrix verify that AT27C040-70PC is sourced from the original manufacturer or authorized distributors?
All AT27C040-70PC 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 AT27C040-70PC meets industry standards.
7.What is the process for return or replacement of AT27C040-70PC?
All AT27C040-70PC units undergo pre-shipment inspection (PSI). If there is an issue with AT27C040-70PC, 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 AT27C040-70PC part is unused and in its original packaging.
Return procedure for AT27C040-70PC:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AT27C040-70PC Tags
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M24C02-WMN6TP
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AT24C02C-XHM-T
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AT21CS01-STUM10-T
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M24C02-FMC6TG
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AT24CS02-SSHM-T
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93LC46BT-I/OT
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