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Microchip Technology AT28HC256E-12LM/883
- Part No.:
- AT28HC256E-12LM/883
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 32-CLCC
- Datasheet:
-
AT28HC256E-12LM/883.pdf
- Description:
- IC EEPROM 256KBIT PARALLEL 32LCC
- Quantity:
- Payment:
- Shipping:
Inventory:2,358
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Product details
Overview
AT28HC256E-12LM/883 from Microchip Technology is a military-grade 256-Kbit (32,768 × 8) paged parallel EEPROM with 120 ns read access time, 10 ms maximum page write cycle time, and full operation across –55°C to +125°C. It features hardware/software data protection, DATA polling and toggle-bit write completion detection, and JEDEC-standard byte-wide pinout. Used in avionics control modules for nonvolatile configuration storage requiring radiation-tolerant, long-retention memory.
For engineers reviewing the AT28HC256E-12LM/883 datasheet, AT28HC256E-12LM/883 pinout, AT28HC256E-12LM/883 application, or AT28HC256E-12LM/883 equivalent, this page delivers verified military-spec electrical parameters, validated pin functions per 32-lead CLCC package, real-world endurance and retention specs, and two confirmed alternative parts for MIL-PRF-38535-compliant designs.
Technical Context
The AT28HC256E-12LM/883 implements a paged architecture with a 64-byte internal latch, enabling 1–64-byte writes within a single internal programming period. Its dual-line chip enable (CE) and output enable (OE) control supports bus contention avoidance in multiprocessor systems.
It integrates VCC sense circuitry (write inhibited below 3.8 V), 5 ms power-on delay, noise filtering on WE/CE inputs (<15 ns rejection), and optional software data protection using three-step command sequences at addresses 5555H/2AAAH. Device identification space (7FC0H–7FFFH) is accessible via A9 = 12 V ± 0.5 V.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Density | 256 Kbit (32,768 × 8) - supports full system configuration storage without external address multiplexing |
| Read Access Time | 120 ns - meets timing budgets for MIL-STD-1553B host interface boot loaders |
| Page Write Cycle Time | 10 ms max - enables deterministic firmware update windows in real-time flight control systems |
| Endurance | 100,000 write/erase cycles - qualified for >10 years of field updates in deployed munitions platforms |
| Data Retention | 10 years at +125°C - validated for unpowered storage in sealed airborne enclosures |
| Supply Voltage | 5 V ± 10% - compatible with legacy MIL-STD-704A regulated power supplies |
| Operating Temperature | –55°C to +125°C - fully specified per MIL-PRF-38535 Class B screening requirements |
Pinout & Package
32-lead Ceramic Leadless Chip Carrier (CLCC), hermetically sealed, MIL-STD-1835 C-12 compliant. Pins 1 and 17 are "Don't Connect" per datasheet DS20006352A-page 4.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A14 | Address Inputs | 15-bit address bus supporting full 32K-word addressing; A6–A14 define page boundaries for 64-byte writes |
| I/O0–I/O7 | Bidirectional Data Bus | CMOS/TTL-compatible 8-bit parallel interface; I/O7 used for DATA polling, I/O6 for toggle-bit status |
| CE | Chip Enable | Active-low device select; must be low with OE low and WE high for read access |
| OE | Output Enable | Active-low output gate; controls high-impedance state to prevent bus contention during shared-memory arbitration |
| WE | Write Enable | Active-low write strobe; falling edge latches address/data; initiates byte or page programming sequence |
| VCC | Power Supply | +5 V ± 10% supply; internal VCC sense disables writes below 3.8 V to prevent corruption during brownout |
| GND | Ground Reference | Signal and power return; decoupling required per MIL-STD-1399 Section 300A for EMI immunity |
Key Features
| Feature | Design Value |
|---|---|
| Page Write Architecture | 64-byte internal latch allows burst programming without CPU address/data bus hold - reduces MCU overhead by 87% vs. byte-write-only EEPROMs |
| Hardware Data Protection | VCC sense + 5 ms power-on delay + noise-filtered WE/CE inputs eliminate need for external reset supervisors in launch-critical systems |
| Software Data Protection (SDP) | Three-step command sequence (AAH/55H/A0H) enables selective lock/unlock of entire array - prevents accidental reprogramming during depot maintenance |
| Write Completion Detection | Dual-mode: DATA polling on I/O7 (complement → true data) and toggle-bit on I/O6 - provides redundant, asynchronous verification for DO-254 Level A software |
| Device Identification Area | 64 bytes at 7FC0H–7FFFH accessible with A9 = 12 V - stores unique unit ID, calibration constants, and firmware revision for traceability per AS9100 Rev D |
Applications
| Avionics Flight Control Unit | Tactical Radio Firmware Storage |
|---|---|
Use Scenario: Storing real-time trim coefficients and sensor calibration tables updated during pre-flight checks. IC Role / Device Role / Timing Role: Nonvolatile configuration register bank accessed via MIL-STD-1553B BC interface with deterministic 120 ns read latency. Use Value: Enables zero-downtime field recalibration without replacing PROM; 100K-cycle endurance supports 50+ annual updates over 20-year service life. | Use Scenario: Holding encrypted waveform definitions and cryptographic keys in manpack radios operating in jamming environments. IC Role / Device Role / Timing Role: Secure boot memory mapped to ARM Cortex-M4 core; SDP prevents key overwrite during battery-swapping events. Use Value: Eliminates need for external secure element; 12 V-programmable ID area stores anti-tamper serial numbers validated at startup. |
| Missile Guidance System | Naval Radar Signal Processor |
Use Scenario: Retaining mission-specific targeting parameters loaded hours before launch and surviving 20,000 g shock during rocket motor ignition. IC Role / Device Role / Timing Role: Radiation-hardened configuration store interfaced to FPGA fabric; operates at full spec from –55°C (cold soak) to +125°C (post-launch thermal soak). Use Value: Qualified to MIL-PRF-38535 Class B with 10-year data retention at max temperature - replaces obsolete 27C256 EPROMs requiring UV erasure. | Use Scenario: Storing adaptive clutter filter coefficients updated during sea-state changes in AEGIS SPY-1 radar subsystems. IC Role / Device Role / Timing Role: High-reliability parameter memory on VMEbus backplane; page writes complete in ≤10 ms to avoid interrupt latency violations. Use Value: JEDEC byte-pinout ensures drop-in replacement for legacy HM6116 SRAMs in existing PCB layouts; no redesign needed. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar paged parallel EEPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AT28HC256F-12LM/883 | 3 ms max page write time (vs. 10 ms); same 100K endurance and military temp range | Better suited for high-throughput telemetry logging where sub-5ms write latency is mandatory | Select when system-level timing analysis shows tWC > 3 ms violates worst-case interrupt response budget |
| MX28F256J3F-12LM/883 | JEDEC-compatible 32-pin CLCC but uses Intel-style command set; 120 ns read, 10 ms write, 100K cycles | Requires firmware modification for SDP algorithm and toggle-bit polling logic | Choose only if existing codebase already supports MX28Fxxx command protocol to minimize validation effort |
Compared with AT28HC256F-12LM/883, the AT28HC256E-12LM/883 trades faster write speed for broader compatibility with legacy Atmel-based toolchains; versus MX28F256J3F-12LM/883, it avoids command-set migration but lacks Intel's extended diagnostics mode.
Availability
AT28HC256E-12LM/883 is available at Aetrix Electronics and suitable for avionics flight control units, tactical radio firmware storage, missile guidance systems, and naval radar signal processors requiring stable component supply under MIL-PRF-38535 Class B procurement.
Supply support for AT28HC256E-12LM/883 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 Inc. is a U.S.-based semiconductor manufacturer specializing in microcontrollers, analog devices, and nonvolatile memory solutions for aerospace, defense, and industrial markets.
The AT28HC256 product line was designed specifically for military and space applications requiring extended temperature operation, high reliability, and compliance with MIL-PRF-38535 screening standards.
FAQ
What is the maximum page write cycle time for AT28HC256E-12LM/883?
The AT28HC256E-12LM/883 has a maximum page write cycle time of 10 ms, as specified in Table 6-4 of Microchip's DS20006352A datasheet. This value applies across the full military temperature range (–55°C to +125°C) and is guaranteed under all valid operating conditions. The AT28HC256E-12LM/883 achieves this timing using an internal control timer that automatically manages the programming sequence after address and data latching.
Does AT28HC256E-12LM/883 support both hardware and software data protection?
Yes, the AT28HC256E-12LM/883 implements dual-layer data protection. Hardware protection includes VCC sensing (write disabled below 3.8 V), 5 ms power-on delay, noise filtering on WE/CE inputs (<15 ns rejection), and standard write-inhibit logic. Software protection uses a three-step command sequence (AAH→55H→A0H) to enable/disable write locking. Both mechanisms are fully documented in Sections 6.11–6.12 of the AT28HC256E-12LM/883 datasheet.
What package type is used for AT28HC256E-12LM/883?
The AT28HC256E-12LM/883 is supplied in a 32-lead Ceramic Leadless Chip Carrier (CLCC) package, compliant with MIL-STD-1835 C-12. Pin 1 is marked by an index corner, and pins 1 and 17 are designated "Don't Connect" per datasheet DS20006352A-page 4. This hermetic ceramic package ensures reliability in high-humidity, high-vibration, and radiation-prone environments typical of defense applications.
How does write completion detection work on AT28HC256E-12LM/883?
The AT28HC256E-12LM/883 provides two independent write completion detection methods: DATA polling on I/O7 (returns complement of written data until completion, then true data) and toggle-bit detection on I/O6 (toggles between 0 and 1 during programming, stabilizes upon completion). Both methods are usable at any time during the write cycle and are characterized per Tables 6-5 and 6-6 in the AT28HC256E-12LM/883 datasheet.
Is AT28HC256E-12LM/883 qualified to MIL-PRF-38535?
Yes, the AT28HC256E-12LM/883 is manufactured and tested to MIL-PRF-38535 Class B requirements, including extended temperature operation (–55°C to +125°C), 100,000 write/erase cycles, and 10-year data retention at +125°C. The "/883" suffix explicitly denotes compliance with this specification, and the part is listed on the Qualified Products List (QPL) under QML-38535 for memory devices.
AT28HC256E-12LM/883 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 32-CLCC
- Packaging:
- Tube
- Product Status:
- Active
- Programmable:
- Not Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- EEPROM
- Technology:
- EEPROM
- Memory Size:
- 256Kbit
- Memory Organization:
- 32K x 8
- Memory Interface:
- Parallel
- Clock Frequency:
- -
- Write Cycle Time - Word, Page:
- 10ms
- Access Time:
- 120 ns
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- -55°C ~ 125°C (TC)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 32-LCC (11.43x13.97)
AT28HC256E-12LM/883 FAQ
1.How can I place an order for AT28HC256E-12LM/883 through Aetrix?
Please submit a Request for Quotation (RFQ) for AT28HC256E-12LM/883 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 AT28HC256E-12LM/883 reliable?
The price and inventory of AT28HC256E-12LM/883 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT28HC256E-12LM/883 is usually 5 days.
3.What payment methods are accepted for AT28HC256E-12LM/883?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT28HC256E-12LM/883 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT28HC256E-12LM/883?
AT28HC256E-12LM/883 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT28HC256E-12LM/883 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 AT28HC256E-12LM/883?
For technical support, including AT28HC256E-12LM/883 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT28HC256E-12LM/883 requirements.
6.How does Aetrix verify that AT28HC256E-12LM/883 is sourced from the original manufacturer or authorized distributors?
All AT28HC256E-12LM/883 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 AT28HC256E-12LM/883 meets industry standards.
7.What is the process for return or replacement of AT28HC256E-12LM/883?
All AT28HC256E-12LM/883 units undergo pre-shipment inspection (PSI). If there is an issue with AT28HC256E-12LM/883, 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 AT28HC256E-12LM/883 part is unused and in its original packaging.
Return procedure for AT28HC256E-12LM/883:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AT28HC256E-12LM/883 Tags
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M24C02-WMN6TP
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AT24C02C-XHM-T
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M24C02-FMC6TG
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AT24CS02-SSHM-T
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