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Microchip Technology AT27C020-90PI
- Part No.:
- AT27C020-90PI
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 32-DIP (0.600", 15.24mm)
- Datasheet:
-
AT27C020-90PI.pdf
- Description:
- IC EPROM 2MBIT PARALLEL 32DIP
- Quantity:
- Payment:
- Shipping:
Inventory:4,892
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Product details
Overview
AT27C020-90PI from Atmel is a 2-Mbit (256K × 8) one-time programmable EPROM optimized for high-speed read access and low-power operation in embedded firmware storage applications. It features 55 ns read access time, 5 V ±10% single-supply operation, and JEDEC-standard 32-lead PDIP packaging. Designed for industrial temperature range (−40°C to +85°C), it supports rapid programming at 100 µs/byte and integrates product identification code for automated programming equipment.
For engineers reviewing the AT27C020-90PI datasheet, AT27C020-90PI pinout, AT27C020-90PI application, or AT27C020-90PI equivalent, key selection criteria include read timing (tACC = 90 ns), standby current (≤100 µA), OTP reliability, industrial-grade temperature support, and compatibility with standard 5 V microprocessor buses requiring no WAIT states.
Technical Context
The AT27C020-90PI implements a CMOS-based OTP EPROM architecture with dual-line control (CE and OE) enabling flexible bus interface management and prevention of contention. Its address space spans A0–A17 (18-bit), supporting full 256K-byte decoding without external logic.
It operates exclusively in 5 V read mode but requires elevated VPP (12.0 V ±0.5 V) during programming, with integrated Rapid™ algorithm ensuring verified byte-level programming in ≤100 µs per byte. Input/output pins are fully CMOS- and TTL-compatible, with VIH up to VCC + 0.5 V and VOL ≤0.4 V at 2.1 mA sink.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 2,097,152 bits (256K × 8) - supports full firmware image storage for 8-bit microcontrollers without bank switching |
| Read Access Time (tACC) | 90 ns max - enables direct interfacing with 10 MHz+ microprocessors without wait-state insertion |
| Supply Voltage | 5 V ±10% - compatible with standard logic rails; no auxiliary voltage required for read operation |
| Standby Current (ISB1) | 100 µA max - minimizes system power draw during idle periods in battery-backed or energy-sensitive designs |
| Active Current (ICC) | 25 mA max at 5 MHz - predictable power budgeting for real-time firmware fetch cycles |
| Programming Speed | 100 µs/byte typical - reduces production programming time versus legacy EPROMs; verified per byte before advancing address |
| ESD Protection | 2,000 V HBM - enhances handling robustness during manufacturing and board assembly |
Pinout & Package
AT27C020-90PI is supplied in a 32-lead, 0.600" wide plastic dual in-line package (PDIP), JEDEC MS-016 compliant, with 0.1" lead pitch and through-hole mounting. Pin 1 is marked by a notch or dot; leads are tin-lead plated for solderability.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A17 | Address Inputs | 18-bit address bus; fully decoded to select any of 256K bytes; TTL/CMOS compatible thresholds |
| O0–O7 | Data Outputs | 8-bit bidirectional data bus outputs; active only when CE and OE are low; high-impedance otherwise |
| CE | Chip Enable | Primary device select; must be low for read or program access; controls power state transition between active/standby |
| OE | Output Enable | Secondary output gate; allows shared bus operation by disabling outputs while CE remains asserted |
| PGM | Program Strobe | Active-low pulse input during programming; initiates 100 µs write cycle when VPP = 12 V and CE = low |
| VPP | Programming Voltage | 12.0 V ±0.5 V input during programming only; must be applied after and removed before VCC per sequencing rules |
| VCC | Power Supply | 5 V ±10% supply for both read and program modes; decoupling requires 0.1 µF ceramic capacitor at pin |
| GND | Ground Reference | Common return path for VCC and VPP; requires low-inductance connection to minimize noise during fast transitions |
Key Features
| Feature | Design Value |
|---|---|
| Rapid™ Programming Algorithm | Guarantees verified byte programming in ≤100 µs with up to 10 re-pulse attempts per failed byte - improves production yield and throughput |
| Integrated Product Identification Code | Two-byte electronic ID (Manufacturer: 0x1E, Device: 0x86) readable via A9/VH and A0 toggle - enables auto-detection and algorithm selection in universal programmers |
| Two-Line Control Architecture | Independent CE and OE inputs allow precise bus arbitration and eliminate contention risks in multi-device systems |
| Industrial Temperature Range | Rated for −40°C to +85°C operation - suitable for factory automation, motor drives, and outdoor embedded controllers |
| High-Reliability Process | 200 mA latch-up immunity and 2,000 V ESD protection - ensures robustness in noisy industrial environments |
Applications
| Industrial PLC Firmware Storage | Automotive Instrument Cluster 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: Nonvolatile firmware storage device providing deterministic 90 ns read access to instruction fetches from 8-bit microcontrollers. Use Value: Eliminates need for external WAIT-state generation, enabling tighter real-time scan cycle timing and reducing BOM count versus flash-based alternatives requiring wear leveling. |
Use Scenario: Holding calibrated display initialization routines and gauge driver code in automotive instrument clusters operating across −40°C to +85°C. IC Role / Device Role / Timing Role: OTP boot ROM delivering verified, unalterable startup code to an 8051-class MCU upon power-on reset. Use Value: Immune to bit corruption from EMI or voltage transients - critical for safety-critical display functions where firmware integrity is mandated. |
| Legacy Microcontroller Upgrade Module | Medical Diagnostic Equipment BIOS |
Use Scenario: Replacing obsolete 27C256 EPROMs in field-upgraded industrial HMIs using identical 32-pin PDIP footprint and 5 V interface. IC Role / Device Role / Timing Role: Drop-in memory replacement preserving existing PCB layout and timing margins due to matched tACC and drive strength. Use Value: Enables lifecycle extension of legacy systems without redesign; supports same programmer hardware via identical ID code protocol. |
Use Scenario: Storing immutable boot firmware and calibration constants in portable ultrasound or ECG devices requiring regulatory traceability. IC Role / Device Role / Timing Role: One-time programmable BIOS ROM ensuring firmware revision lock and audit trail compliance per IEC 62304. Use Value: Prevents accidental or malicious firmware modification post-manufacture - satisfies Class B software safety requirements. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar OTP EPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AT27C020-90JI | Same die, PLCC package (32J); identical AC/DC specs and programming algorithm | Suitable for surface-mount designs with space-constrained layouts; requires reflow-compatible PCB design | Select when upgrading from through-hole to SMT or when board area is limited - no firmware or timing changes needed |
| AM27C256B-90DC | 256K × 8 OTP EPROM; 90 ns access; 5 V only; no integrated ID code; different pinout (VPP on pin 28 vs. pin 1 on AT27C020) | Lacks Rapid™ programming and product ID; requires manual algorithm selection in programmers | Choose only if legacy tooling mandates AMD-compatible devices; verify pin mapping and VPP sequencing separately |
Compared with AT27C020-90PI, the AT27C020-90JI offers identical functionality in PLCC for SMT migration, while AM27C256B-90DC provides a functionally similar but less feature-rich alternative lacking ID code and requiring pinout adaptation - making AT27C020-90PI preferable for new designs needing programming automation and industrial reliability.
Availability
AT27C020-90PI is available at Aetrix Electronics and suitable for industrial control systems, automotive instrumentation, medical diagnostic devices, and legacy system upgrades requiring stable component supply and long-term obsolescence management.
Supply support for AT27C020-90PI 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 programmable logic, acquired by Microchip Technology in 2016. Its legacy memory products remain widely supported in industrial and automotive applications.
The AT27C020 belongs to Atmel's 27C-series OTP EPROM family, designed specifically for reliable, high-speed firmware storage in cost-sensitive embedded systems where code immutability, deterministic timing, and industrial temperature resilience are mandatory.
FAQ
What is the maximum operating temperature range for the AT27C020-90PI?
The AT27C020-90PI is rated for industrial temperature operation from −40°C to +85°C. This specification is confirmed in the Ordering Information table and DC Operating Conditions section of the datasheet. The "I" suffix in the part number explicitly denotes industrial grade. Operation outside this range may result in parametric noncompliance or accelerated wear.
Does the AT27C020-90PI require a separate programming voltage during normal read operation?
No, the AT27C020-90PI requires only a single 5 V ±10% supply (VCC) for read mode operation. VPP (12.0 V ±0.5 V) is used exclusively during programming and must be disconnected or held at 5 V during read cycles. The datasheet specifies that VPP may be tied directly to VCC except during programming, with total supply current being the sum of ICC and IPP.
How does the Rapid™ Programming Algorithm improve production efficiency for the AT27C020-90PI?
The Rapid™ Programming Algorithm reduces AT27C020-90PI programming time to 100 µs per byte (typical), with automatic verification and up to 10 re-pulse attempts per failing byte. This eliminates manual verification steps and increases first-pass yield. The algorithm is implemented in hardware and requires no external controller logic - only proper VPP sequencing and PGM pulse timing per the AC Programming Characteristics table.
Can the AT27C020-90PI be used as a direct replacement for the AT27C020-90PC?
Yes, the AT27C020-90PI and AT27C020-90PC share identical electrical specifications, timing parameters (including tACC = 90 ns), pinout, and programming behavior. The only difference is temperature grade: "I" denotes industrial (−40°C to +85°C), while "C" denotes commercial (0°C to +70°C). For industrial environments, AT27C020-90PI is the appropriate drop-in replacement.
What decoupling capacitance is required for stable operation of the AT27C020-90PI?
The AT27C020-90PI requires a 0.1 µF high-frequency ceramic capacitor placed between VCC and GND, mounted as close as possible to the device pins. For boards with multiple EPROMs, a 4.7 µF bulk electrolytic capacitor should also be added near the power entry point. These values are specified in the "System Considerations" section to suppress transient excursions during CE toggling and ensure reliable read/write margins.
AT27C020-90PI 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:
- 2Mbit
- Memory Organization:
- 256K x 8
- Memory Interface:
- Parallel
- Clock Frequency:
- -
- Write Cycle Time - Word, Page:
- -
- Access Time:
- 90 ns
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- -40°C ~ 85°C (TC)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 32-PDIP
AT27C020-90PI FAQ
1.How can I place an order for AT27C020-90PI through Aetrix?
Please submit a Request for Quotation (RFQ) for AT27C020-90PI 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 AT27C020-90PI reliable?
The price and inventory of AT27C020-90PI are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT27C020-90PI is usually 5 days.
3.What payment methods are accepted for AT27C020-90PI?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT27C020-90PI transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT27C020-90PI?
AT27C020-90PI orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT27C020-90PI 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 AT27C020-90PI?
For technical support, including AT27C020-90PI datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT27C020-90PI requirements.
6.How does Aetrix verify that AT27C020-90PI is sourced from the original manufacturer or authorized distributors?
All AT27C020-90PI 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 AT27C020-90PI meets industry standards.
7.What is the process for return or replacement of AT27C020-90PI?
All AT27C020-90PI units undergo pre-shipment inspection (PSI). If there is an issue with AT27C020-90PI, 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 AT27C020-90PI part is unused and in its original packaging.
Return procedure for AT27C020-90PI:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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