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Microchip Technology AT27LV256A-70RC
- Part No.:
- AT27LV256A-70RC
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 28-SOIC (0.342", 8.69mm Width)
- Datasheet:
-
AT27LV256A-70RC.pdf
- Description:
- IC EPROM 256KBIT PARALLEL 28SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:4,101
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Product details
Overview
AT27LV256A-70RC from Atmel is a 256K-bit (32K × 8) low-voltage one-time programmable EPROM with 70 ns read access time, dual 3.0–3.6 V or 4.5–5.5 V supply operation, and JEDEC-standard 28-lead SOIC packaging. It delivers TTL-compatible outputs at 3.0 V and supports rapid programming at 100 µs/byte, making it ideal for battery-powered portable systems requiring nonvolatile code storage.
For engineers reviewing the AT27LV256A-70RC datasheet, AT27LV256A-70RC pinout, AT27LV256A-70RC application, or AT27LV256A-70RC equivalent, key selection criteria include its 70 ns tACC timing under 3.3 V, <20 µA standby current, pin compatibility with AT27C256R, dual-voltage flexibility, and industry-standard SOIC-28 footprint for legacy system upgrades and mixed-supply embedded designs.
Technical Context
The AT27LV256A-70RC implements a CMOS OTP EPROM architecture with two-line control (CE/OE), enabling bus contention prevention in shared-memory systems. Its read cycle relies on address-valid-to-output-delay (tACC = 70 ns max) and CE/OE-selectable output enable timing, supporting both CMOS and TTL logic families across voltage ranges.
Programming uses a dedicated VPP = 13.0 V supply with Rapid™ algorithm - each byte requires a 95–105 µs CE pulse followed by verify-reprogram loops. Product identification is accessed via A9 = 12.0 V and A0 toggling, returning manufacturer (0x1E) and device code (0x8C) bytes compatible with AT27C256R.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 256 Kbit (32K × 8) - provides sufficient space for boot code or firmware in microcontroller-based systems without external memory expansion. |
| Read Access Time | 70 ns max at VCC = 3.0–3.6 V - enables direct interface with 10–14 MHz microcontrollers without wait states. |
| Supply Voltage Range | 3.0–3.6 V or 4.5–5.5 V - allows seamless integration into dual-voltage platforms such as PC cards or hot-pluggable peripherals. |
| Standby Current | 20 µA max at VCC = 3.6 V - reduces quiescent power in always-on embedded systems like remote sensors or IoT edge nodes. |
| Operating Temperature | -40°C to +85°C - qualified for industrial-grade applications including factory automation and automotive body control modules. |
| Package Type | 28-lead SOIC (0.330" wide) - matches JEDEC MS-012 standard for drop-in replacement of legacy 27C256 devices on existing PCBs. |
| Programming Speed | 100 µs/byte typical - cuts firmware update time during manufacturing programming by >5× versus conventional EPROMs. |
Pinout & Package
AT27LV256A-70RC is supplied in a 28-lead plastic gull-wing small outline integrated circuit (SOIC) package per JEDEC MS-012, measuring 0.330" wide with 0.050" lead pitch. Pin 1 is marked by a notch or dot; leads are numbered counter-clockwise from pin 1.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A14 | Address Inputs | 15-bit address bus accepting 0–32767 to select one of 32K bytes; TTL/CMOS compatible thresholds ensure reliable decoding with 3.3 V or 5 V controllers. |
| O0–O7 | Data Outputs | 8-bit bidirectional data bus delivering stored byte on read; VOH ≥ 2.4 V at IOH = −2.0 mA ensures noise margin with 3.3 V LVTTL receivers. |
| CE | Chip Enable | Active-low chip select enabling full device access; VIH ≥ 2.0 V allows direct connection to 3.3 V GPIO without level shifting. |
| OE | Output Enable | Active-low output gate controlling O0–O7 drive state; decouples memory from data bus during transfers to prevent contention. |
| VCC | Power Supply | Primary supply input supporting dual ranges (3.0–3.6 V or 4.5–5.5 V); requires local 0.1 µF ceramic bypass capacitor per device. |
| GND | Ground Reference | Signal and power return path; must be connected before VPP during programming to avoid latchup. |
| VPP | Programming Voltage | 13.0 V ± 0.25 V input used only during programming; requires external 0.1 µF capacitor to ground to suppress transients. |
| NC | No Connect | Pins 1 and 17 in PLCC variant are unconnected; not present in SOIC-28 package - no NC pins in AT27LV256A-70RC. |
Key Features
| Feature | Design Value |
|---|---|
| Rapid™ Programming Algorithm | Reduces production programming time to ~100 µs/byte with built-in verify-reprogram loop, minimizing test floor dwell time and increasing yield. |
| Dual-Voltage Read Operation | Operates natively at 3.3 V while delivering TTL-level outputs compatible with 5 V systems - eliminates need for level translators in mixed-supply boards. |
| Integrated Product ID Code | Electronic manufacturer (0x1E) and device (0x8C) codes accessible via A9 = 12 V and A0 toggle - enables automated programmer validation and BOM traceability. |
| JEDEC Pin Compatibility | Pin-for-pin identical to AT27C256R - allows direct substitution in legacy 5 V designs without layout changes or signal integrity revalidation. |
| High-Reliability Process | 2000 V HBM ESD rating and 200 mA latchup immunity ensure robustness in handling and field operation across industrial environments. |
Applications
| Industrial Control Firmware Storage | PCMCIA Card Boot Memory |
|---|---|
Use Scenario: Storing boot firmware and configuration tables in programmable logic controllers (PLCs) operating in harsh factory environments. IC Role / Device Role / Timing Role: Nonvolatile code storage with 70 ns read access enabling deterministic startup and real-time task loading. Use Value: Industrial temperature range (-40°C to +85°C) and 20 µA standby current support unattended operation in sealed enclosures with limited thermal dissipation. | Use Scenario: Providing initialization code for PCMCIA Type II peripheral cards used in laptops and portable test equipment. IC Role / Device Role / Timing Role: OTP EPROM serving as primary boot ROM, interfaced directly to host controller's 8-bit data bus and address lines. Use Value: Dual-voltage operation (3.3 V/5 V) ensures plug-and-play compatibility with both 3.3 V and 5 V host slots without hardware modification. |
| Legacy System Memory Upgrade | Embedded Instrumentation Calibration Data |
Use Scenario: Replacing obsolete 27C256 EPROMs in aging medical imaging or telecom infrastructure equipment. IC Role / Device Role / Timing Role: Pin-compatible drop-in replacement preserving original timing margins and PCB layout. Use Value: Identical pinout and JEDEC SOIC-28 footprint eliminates redesign cost and qualification delays for end-of-life component mitigation. | Use Scenario: Holding factory-calibrated sensor coefficients and linearization tables in handheld multimeters and oscilloscopes. IC Role / Device Role / Timing Role: Secure, tamper-resistant storage of precision calibration constants accessed during power-up self-test. Use Value: One-time programmability prevents accidental overwrites; low standby current extends battery life between calibrations. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar OTP EPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AT27C256R-70PC | 5 V-only operation (4.5–5.5 V), no 3.3 V support; same 70 ns speed and SOIC-28 package. | Requires dedicated 5 V rail; unsuitable for battery-powered or mixed-voltage systems. | Select when legacy 5 V design has no voltage scaling constraints and lowest-cost sourcing is priority. |
| MN65E256APL | Same 256K × 8 OTP EPROM function but with 90 ns access time and different pinout (PLCC-32 only). | Lacks SOIC-28 option; incompatible pin mapping prevents PCB reuse. | Consider only if PLCC-32 footprint is available and 90 ns timing satisfies system requirements. |
Compared with AT27LV256A-70RC, AT27C256R-70PC offers identical speed and footprint but sacrifices low-voltage operation, while MN65E256APL retains OTP functionality but introduces layout incompatibility and slower timing - making AT27LV256A-70RC the sole choice for 3.3 V–compatible, SOIC-28–based upgrades.
Availability
AT27LV256A-70RC is available at Aetrix Electronics and suitable for industrial control firmware storage, PCMCIA card boot memory, and legacy system memory upgrades requiring stable component supply across extended product lifecycles.
Supply support for AT27LV256A-70RC 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 secure authentication ICs before its acquisition by Microchip Technology in 2016.
The AT27LV256A belongs to Atmel's low-voltage OTP EPROM product line, designed specifically to extend battery life and simplify power architecture in portable and mixed-supply embedded systems while maintaining backward compatibility with 5 V EPROM standards.
FAQ
What is the maximum read access time specified for the AT27LV256A-70RC?
The AT27LV256A-70RC has a maximum read access time (tACC) of 70 ns when operated at VCC = 3.0–3.6 V or 4.5–5.5 V, measured from address valid to valid data output under CE = OE = VIL conditions. This timing is guaranteed across the full industrial temperature range (-40°C to +85°C) and defines the upper limit for zero-wait-state interface with microcontrollers running up to ~14 MHz.
Does the AT27LV256A-70RC support both 3.3 V and 5 V operation simultaneously?
No - the AT27LV256A-70RC operates in either 3.0–3.6 V or 4.5–5.5 V supply mode, but not both at once. However, it produces TTL-compatible outputs at 3.3 V that interface directly with 5 V logic, enabling use in dual-rail systems where the host controller runs at 5 V while the AT27LV256A-70RC is powered from a 3.3 V supply.
Can the AT27LV256A-70RC be programmed using standard EPROM programmers?
Yes - the AT27LV256A-70RC programs identically to the AT27C256R and uses the same programming equipment. It requires VPP = 13.0 V and VCC = 6.5 V during programming, with a 95–105 µs CE pulse width per byte. Its Integrated Product Identification Code (0x1E/0x8C) ensures automatic algorithm selection in compliant programmers.
What package type is used for the AT27LV256A-70RC?
The AT27LV256A-70RC is packaged in a 28-lead plastic gull-wing small outline integrated circuit (SOIC) with 0.330" body width, conforming to JEDEC MS-012. This package is pin-identical to the SOIC variants of AT27C256R and supports surface-mount assembly using standard reflow profiles.
Is the AT27LV256A-70RC suitable for industrial temperature applications?
Yes - the AT27LV256A-70RC is rated for operation from -40°C to +85°C, meeting industrial temperature specifications. Its high-reliability CMOS process includes 2000 V HBM ESD protection and 200 mA latchup immunity, ensuring robust performance in factory automation, motor drives, and outdoor instrumentation environments.
AT27LV256A-70RC Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 28-SOIC (0.342", 8.69mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- EPROM
- Technology:
- EPROM - OTP
- Memory Size:
- 256Kbit
- Memory Organization:
- 32K x 8
- Memory Interface:
- Parallel
- Clock Frequency:
- -
- Write Cycle Time - Word, Page:
- -
- Access Time:
- 70 ns
- Voltage - Supply:
- 3V ~ 3.6V, 4.5V ~ 5.5V
- Operating Temperature:
- 0°C ~ 70°C (TC)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 28-SOIC
AT27LV256A-70RC FAQ
1.How can I place an order for AT27LV256A-70RC through Aetrix?
Please submit a Request for Quotation (RFQ) for AT27LV256A-70RC 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 AT27LV256A-70RC reliable?
The price and inventory of AT27LV256A-70RC are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT27LV256A-70RC is usually 5 days.
3.What payment methods are accepted for AT27LV256A-70RC?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT27LV256A-70RC transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT27LV256A-70RC?
AT27LV256A-70RC orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT27LV256A-70RC 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 AT27LV256A-70RC?
For technical support, including AT27LV256A-70RC datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT27LV256A-70RC requirements.
6.How does Aetrix verify that AT27LV256A-70RC is sourced from the original manufacturer or authorized distributors?
All AT27LV256A-70RC 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 AT27LV256A-70RC meets industry standards.
7.What is the process for return or replacement of AT27LV256A-70RC?
All AT27LV256A-70RC units undergo pre-shipment inspection (PSI). If there is an issue with AT27LV256A-70RC, 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 AT27LV256A-70RC part is unused and in its original packaging.
Return procedure for AT27LV256A-70RC:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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