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Microchip Technology AT27C040-90PC
- Part No.:
- AT27C040-90PC
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 32-DIP (0.600", 15.24mm)
- Datasheet:
-
AT27C040-90PC.pdf
- Description:
- IC EPROM 4MBIT PARALLEL 32DIP
- Quantity:
- Payment:
- Shipping:
Inventory:1,157
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Product details
Overview
AT27C040-90PC from Atmel is a 4-Mbit (512K × 8) one-time programmable EPROM designed for nonvolatile program storage in microprocessor systems. It operates on a single 5V ±10% supply, delivers 90 ns read access time, draws ≤100 µA standby current, and supports commercial temperature range (0°C to 70°C) in a 32-lead PDIP package. It serves as firmware storage in legacy embedded controllers requiring reliable, low-power, pin-compatible ROM replacement.
For engineers reviewing the AT27C040-90PC datasheet, AT27C040-90PC pinout, AT27C040-90PC application, or AT27C040-90PC equivalent, key selection criteria include verified 90 ns tACC timing, JEDEC-standard 32P6 PDIP footprint compatibility, CMOS/TTL I/O interface support, VPP programming voltage handling (12.0 V ±0.5 V), and Rapid™ algorithm compliance (100 µs/byte typical).
Technical Context
The AT27C040-90PC implements a two-line control architecture using CE (Chip Enable) and OE (Output Enable) to manage bus contention during high-speed read cycles. Its address decoding covers A0–A18 for full 512K-byte access, with dedicated VPP pin for 12 V programming voltage injection.
It uses Atmel's scaled CMOS process to achieve low active power (≤30 mA at 5 MHz) and high reliability features including 2000 V ESD protection and 200 mA latchup immunity. The integrated product identification code (Manufacturer ID = 0x1E, Device ID = 0x0B) enables automatic algorithm selection in industry-standard programmers.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 4,194,304-bit (512K × 8) OTP EPROM - provides full firmware image storage for 8-bit microcontrollers without external address latching. |
| Read Access Time | 90 ns max (tACC) - eliminates WAIT states in 80C51, Z80, and 68K-based systems running ≤11 MHz. |
| Supply Voltage | 5 V ±10% - compatible with standard TTL/CMOS logic rails; no auxiliary voltage regulators required. |
| Standby Current | 100 µA max - enables low-power retention in battery-backed or intermittently powered systems. |
| Programming Voltage | VPP = 12.0 V ±0.5 V - requires dedicated programming hardware; not used during normal read operation. |
| Operating Temp | 0°C to 70°C - validated for commercial-grade industrial control panels and office equipment. |
| I/O Compatibility | CMOS and TTL - interfaces directly with 74LS, 74HC, and microcontroller GPIO without level-shifting. |
Pinout & Package
AT27C040-90PC is packaged in a 32-lead, 0.600" wide plastic dual in-line package (PDIP), per JEDEC MS-001, designated 32P6. Pin 1 is marked by a notch or dot; leads are spaced 0.100" (2.54 mm) apart.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A18 | Address Inputs | 19-bit address bus supporting full 512K-byte decode; A0 = LSB, A18 = MSB. |
| O0–O7 | Data Outputs | 8-bit bidirectional data bus in read mode; high-impedance when CE or OE inactive. |
| CE | Chip Enable | Active-low global enable; must be asserted before OE to avoid bus contention. |
| OE | Output Enable | Active-low output gate; controls data bus drive timing independently of CE. |
| VPP | Programming Voltage | 12 V input during programming only; tied to VCC (5 V) during read operation. |
| VCC | Power Supply | +5 V main supply; must be applied simultaneously with or before VPP during programming. |
| GND | Ground | Reference return path for all signals and supplies; requires local 0.1 µF ceramic decoupling. |
Key Features
| Feature | Design Value |
|---|---|
| Rapid™ Programming Algorithm | 100 µs/byte typical programming time - reduces production burn-in cycle duration by >90% vs. legacy EPROMs. |
| Integrated Product ID Code | Manufacturer ID = 0x1E, Device ID = 0x0B - enables auto-detection and algorithm matching in universal programmers (e.g., Data I/O PS-200). |
| Two-Line Control (CE/OE) | Independent chip and output gating - prevents bus conflicts in multiplexed memory systems with shared data buses. |
| High-Reliability CMOS | 2000 V HBM ESD rating and 200 mA latchup immunity - ensures robustness in manual handling and noisy industrial environments. |
| JEDEC Standard Packages | 32P6 PDIP footprint - allows drop-in replacement of obsolete 27C4001, 27C040, and AM27C040 variants in existing PCBs. |
Applications
| Industrial PLC Firmware Storage | Legacy PC BIOS Backup |
|---|---|
Use Scenario: Storing ladder logic and I/O configuration in modular programmable logic controllers deployed in factory automation lines. IC Role / Device Role / Timing Role: Nonvolatile program memory providing deterministic 90 ns instruction fetch latency to ensure scan-cycle timing compliance. Use Value: Enables field-upgradeable firmware without redesigning PCB layout due to JEDEC 32P6 pinout compatibility. | Use Scenario: Holding boot-time initialization code and hardware configuration tables in ISA-bus based industrial PCs and embedded workstations. IC Role / Device Role / Timing Role: Primary ROM device mapped to 0xF0000–0xFFFFF address space; accessed via 80286/386 CPU with no wait-state insertion. Use Value: Guarantees <90 ns tACC and CMOS/TTL I/O compatibility, eliminating need for bus buffers or timing adapters. |
| Medical Instrument Bootloader | Avionics Test Equipment Memory |
Use Scenario: Hosting secure bootloader and calibration constants in FDA-cleared diagnostic devices where firmware integrity is auditable and unalterable post-programming. IC Role / Device Role / Timing Role: One-time programmable storage ensuring immutable firmware execution; accessed during power-on reset sequence. Use Value: Leverages OTP architecture to prevent accidental or malicious reprogramming - critical for regulatory traceability. | Use Scenario: Providing test pattern generation firmware and self-test routines in ground-support ATE used for radar transceiver module validation. IC Role / Device Role / Timing Role: High-reliability ROM interfacing with FPGA-based controller over parallel bus; timing-critical for synchronized stimulus delivery. Use Value: Delivers 200 mA latchup immunity and 2000 V ESD protection - essential for lab environments with frequent probe contact and static discharge events. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar OTP EPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AM27C040-90DC | Same 512K×8 organization, 90 ns speed grade, and 32-pin PDIP; differs in manufacturer-specific programming voltage tolerance (12.5 V vs. 12.0 V). | Validated in AMD-based legacy systems; may require minor programmer voltage adjustment. | Select when maintaining AMD-design heritage or sourcing from AMD-qualified distributors. |
| MX27C4001-90PC | Functionally identical 4-Mbit OTP EPROM; same pinout and AC timing, but rated for 100 µA max ISB (vs. 100 µA typical for AT27C040-90PC). | Used in telecom line cards where extended standby current consistency is specified. | Choose when BOM requires second-source qualification under MIL-PRF-38535 screening or extended temp testing. |
Compared with AM27C040-90DC and MX27C4001-90PC, the AT27C040-90PC offers tighter VPP specification (12.0 V ±0.5 V), integrated product ID code for automated programming, and documented Rapid™ algorithm support - making it preferred for high-volume, auto-programmed production lines.
Availability
AT27C040-90PC is available at Aetrix Electronics and suitable for industrial PLC firmware storage, legacy PC BIOS backup, and medical instrument bootloader applications requiring stable component supply across long-lifecycle programs.
Supply support for AT27C040-90PC 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, nonvolatile memory, and RF solutions before its acquisition by Microchip Technology in 2016.
The AT27C040 belongs to Atmel's OTP EPROM product line, engineered for cost-sensitive, high-reliability firmware storage in industrial and computing systems where field reprogrammability is unnecessary.
FAQ
What is the maximum allowed VPP voltage for programming the AT27C040-90PC?
The AT27C040-90PC requires VPP = 12.0 V ±0.5 V during programming, as specified in the DC Programming Characteristics table. Exceeding 12.5 V risks permanent damage; applying VPP before VCC or removing it first violates absolute maximum ratings and may cause internal latchup. Always verify VPP stability with oscilloscope monitoring during programming cycles.
Does the AT27C040-90PC support byte-level programming or only full-chip erase?
The AT27C040-90PC is a one-time programmable (OTP) EPROM and does not support erasure - it has no UV window or electrical erase function. Programming is performed byte-by-byte using the Rapid™ algorithm (100 µs/byte typical), with verification after each pulse. Once programmed, data is permanently stored and cannot be altered or erased.
Can the AT27C040-90PC operate reliably at 5.5 V supply voltage?
Yes - the AT27C040-90PC is rated for 5 V ±10%, meaning it supports 4.5 V to 5.5 V operation. At 5.5 V, ICC active current remains within 30 mA limit and tACC stays ≤90 ns. However, VPP must still be precisely 12.0 V ±0.5 V during programming; VCC and VPP supplies must be sequenced correctly (VCC applied before VPP, removed after).
Is the AT27C040-90PC pin-compatible with the AT27C040-70PC?
Yes - both AT27C040-90PC and AT27C040-70PC share identical pinout, package (32P6 PDIP), and functional interface. The only difference is read access time: 90 ns vs. 70 ns. Systems designed for the -70 variant will operate correctly with the -90PC, though maximum system clock frequency may be reduced accordingly.
What decoupling capacitance is required for stable operation of the AT27C040-90PC?
The AT27C040-90PC requires a minimum 0.1 µF high-frequency ceramic capacitor between VCC and GND, placed as close as possible to the device pins. For boards with multiple EPROMs or high-current peripherals, a bulk 4.7 µF electrolytic capacitor should also be added near the power entry point to suppress low-frequency ripple and transient droop during CE assertion.
AT27C040-90PC 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:
- 90 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
AT27C040-90PC FAQ
1.How can I place an order for AT27C040-90PC through Aetrix?
Please submit a Request for Quotation (RFQ) for AT27C040-90PC 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 AT27C040-90PC reliable?
The price and inventory of AT27C040-90PC are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT27C040-90PC is usually 5 days.
3.What payment methods are accepted for AT27C040-90PC?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT27C040-90PC transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT27C040-90PC?
AT27C040-90PC orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT27C040-90PC 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 AT27C040-90PC?
For technical support, including AT27C040-90PC datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT27C040-90PC requirements.
6.How does Aetrix verify that AT27C040-90PC is sourced from the original manufacturer or authorized distributors?
All AT27C040-90PC 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 AT27C040-90PC meets industry standards.
7.What is the process for return or replacement of AT27C040-90PC?
All AT27C040-90PC units undergo pre-shipment inspection (PSI). If there is an issue with AT27C040-90PC, 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 AT27C040-90PC part is unused and in its original packaging.
Return procedure for AT27C040-90PC:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AT27C040-90PC Tags
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AT24C02C-XHM-T
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AT21CS01-STUM10-T
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