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STMicroelectronics M27C64A-20F1
- Part No.:
- M27C64A-20F1
- Manufacturer:
- STMicroelectronics
- Category:
- Memory
- Package:
- 28-CDIP (0.600", 15.24mm) Window
- Datasheet:
-
M27C64A-20F1.pdf
- Description:
- IC EPROM 64KBIT PARALLEL 28CDIP
- Quantity:
- Payment:
- Shipping:
Inventory:4,660
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Product details
Overview
M27C64A-20F1 from STMicroelectronics is a 64 Kbit (8K × 8) UV-erasable EPROM in FDIP28W ceramic frit-seal package with window, featuring 100 ns access time, 5 V ±10% read supply, active current of 30 mA, standby current of 100 µA, and 12.5 V ±0.25 V programming voltage - used for firmware storage in legacy microprocessor systems requiring field-erasable nonvolatile code retention.
For engineers reviewing the M27C64A-20F1 datasheet, M27C64A-20F1 pinout, M27C64A-20F1 application, or M27C64A-20F1 equivalent, this page delivers verified electrical specs, dual-line output control behavior, UV erasure requirements, electronic signature codes (9Bh/08h), and ECOPACK® lead-free compliance details critical for legacy system maintenance and replacement sourcing.
Technical Context
The M27C64A-20F1 operates in five distinct modes - Read, Standby, Program, Verify, and Electronic Signature - each governed by specific voltage and timing conditions on E (Chip Enable), G (Output Enable), P (Program), and VPP (12.5 V). Its two-line output control architecture decouples device selection (E) from output gating (G), enabling low-power memory arrays without bus contention.
It supports TTL-level address/data inputs and features CMOS-compatible standby current (100 µA), programmable via parallel 8-bit data writes to Q0–Q7 while in Program mode (VPP = 12.5 V, E = VIL, P pulsed). Erasure requires UV exposure (2537 Å, ≥15 W·s/cm²), and electronic signature verification uses A9 = 12 V to read manufacturer code 9Bh and device code 08h.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 64 Kbit (8,192 × 8 organization) - supports full 13-bit address space for 8-bit microprocessor data buses. |
| Access Time | 100 ns (tAVQV) - ensures compatibility with 10 MHz CPU bus cycles in legacy Z80/8086 systems. |
| Read Supply | 5 V ±10% (VCC) - operates directly from standard logic rail without regulation overhead. |
| Programming Voltage | 12.5 V ±0.25 V (VPP) - requires dedicated high-voltage programming circuitry; not compatible with 5 V-only systems. |
| Standby Current | 100 µA (CMOS E > VCC – 0.2 V) - enables ultra-low power retention during processor idle states. |
| Electronic Signature | Manufacturer Code 9Bh, Device Code 08h - enables automatic algorithm selection in universal EPROM programmers. |
| UV Erase Dose | ≥15 W·s/cm² at 2537 Å - defines minimum UV lamp intensity × exposure time to fully reset all bits to '1'. |
Pinout & Package
FDIP28W (28-pin Ceramic Frit-Seal Dual In-line Package with UV-transparent window) - hermetically sealed, designed for repeated UV erasure cycles; window must remain uncovered during erasure and protected from ambient UV during operation.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A12 | Address Inputs | 13-bit address bus interface; latched internally on E/G assertion for memory location selection. |
| Q0–Q7 | Data Outputs | Bi-directional during programming (data input), output-only during read; TTL-compatible drive strength. |
| E | Chip Enable | Primary device select; VIH places device in standby (100 µA), VIL enables internal logic and memory array. |
| G | Output Enable | Secondary output gate; controls Q0–Q7 drive state independently of E - enables shared data bus arbitration. |
| P | Program Control | Active-low pulse input; initiates programming cycle only when VPP = 12.5 V and E = VIL. |
| VPP | Programming Supply | 12.5 V ±0.25 V input; must be stable before and after programming pulse; isolated from VCC path. |
| VCC / VSS | Power / Ground | 5 V read supply (VCC); decoupling requires 0.1 µF ceramic + 4.7 µF bulk per 8 devices to suppress transient spikes. |
| A9 (ES) | Electronic Signature Input | Receives 12 V for signature readout; not used in normal operation - must be isolated from 5 V logic during ES mode. |
Key Features
| Feature | Design Value |
|---|---|
| Dual-line output control (E + G) | Enables zero-bus-contention memory expansion: E selects device into low-power standby, G gates outputs only when data is needed. |
| UV-erasable architecture | FDIP28W window allows full bit-pattern reset using commercial 2537 Å UV lamps - essential for firmware iteration in pre-flash development environments. |
| Electronic signature (9Bh/08h) | Enables auto-detection in programming hardware - eliminates manual part selection and prevents incorrect algorithm application. |
| ECOPACK® lead-free packaging | Meets JEDEC JESD97 second-level interconnect marking; compliant with RoHS Directive 2011/65/EU for legacy system requalification. |
| High-speed programming (<1 min) | Uses multi-pulse verify-and-reprogram algorithm - reduces production programming time vs. traditional single-pass methods. |
Applications
| Industrial PLC Firmware Storage | Legacy Medical Device Boot Code |
|---|---|
|
Use Scenario: Storing fixed boot firmware and I/O configuration tables in DIN-rail mounted programmable logic controllers deployed in factory automation. IC Role / Device Role / Timing Role: Nonvolatile program memory mapped to CPU address space; accessed during power-on reset sequence with strict 100 ns timing window. Use Value: UV erasability allows field updates when logic changes occur between production batches - avoids costly PCB respins. |
Use Scenario: Holding diagnostic self-test routines and calibration constants in Class II medical instruments with long product lifecycles (10+ years). IC Role / Device Role / Timing Role: Read-only instruction store executing during cold start; requires guaranteed data retention over 15-year shelf life under controlled storage. Use Value: Ceramic FDIP28W package provides hermetic sealing against humidity-induced bit corruption - critical for regulatory traceability. |
| Avionics Maintenance Terminal BIOS | Test Equipment PROM Emulation |
|
Use Scenario: Embedded BIOS in portable aircraft maintenance terminals used for engine parameter readout and fault logging in hangar environments. IC Role / Device Role / Timing Role: Memory-mapped firmware executed directly by 80C88 CPU; timing-critical due to real-time response requirements for sensor polling. Use Value: 100 µA standby current extends battery runtime during intermittent use - enables 72-hour operational readiness without recharge. |
Use Scenario: Replacing obsolete mask ROMs in automated test equipment (ATE) handlers where firmware patches are applied infrequently but require physical reprogramming. IC Role / Device Role / Timing Role: Pin-compatible drop-in substitute for older 2764/27128 EPROMs; retains same address/data bus loading and timing margins. Use Value: Electronic signature (9Bh/08h) ensures compatibility with existing ATE programmer software - no toolchain modification required. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar EPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AM27C64A-20DMB | Same 64 Kbit ×8 organization, 100 ns access, but uses plastic DIP-28 (no UV window); programming voltage 12.5 V. | OTP-only - cannot be erased or reprogrammed; suitable only for final production runs with zero firmware change risk. | Select when field reprogrammability is unnecessary and cost sensitivity outweighs erasure flexibility. |
| AT27C64A-20PU | 64 Kbit ×8, 100 ns, 5 V read, 12.5 V program; same pinout; Atmel-manufactured with identical electronic signature protocol. | Discontinued but widely available in surplus channels; minor differences in UV erase endurance (100 vs. 50 cycles) and leakage specs. | Valid functional substitute where ST-branded authenticity is not mandated by OEM qualification requirements. |
Compared with AM27C64A-20DMB (OTP-only) and AT27C64A-20PU (same spec, alternate source), the M27C64A-20F1 uniquely supports field-erasable firmware updates via its FDIP28W UV window - making it the sole choice for applications requiring post-deployment code correction without hardware replacement.
Availability
M27C64A-20F1 is available at Aetrix Electronics and suitable for industrial PLC firmware storage, legacy medical device boot code, avionics maintenance terminal BIOS, and test equipment PROM emulation requiring stable component supply across extended lifecycle programs.
Supply support for M27C64A-20F1 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
STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, MCU, power, and memory products for industrial, automotive, and consumer markets.
The M27C64A belongs to ST's legacy EPROM product line, engineered specifically for reliable, field-erasable nonvolatile storage in microprocessor-based systems where flash memory was unavailable or unsuitable - emphasizing UV endurance, timing predictability, and programmer interoperability.
FAQ
What UV wavelength and exposure time are required to fully erase the M27C64A-20F1?
The M27C64A-20F1 requires short-wave ultraviolet light at 2537 Å with a minimum integrated dose of 15 W·s/cm². Using a standard 12,000 µW/cm² UV lamp, erasure takes 15–20 minutes at 2.5 cm distance. Ambient fluorescent lighting may cause partial erasure over years; direct sunlight can erase it in ~1 week - opaque window labels are recommended for long-term storage.
Can the M27C64A-20F1 be programmed using standard 5 V-only programmers?
No. Programming requires a dedicated 12.5 V ±0.25 V supply on VPP and 6 V ±0.25 V on VCC - both must be applied before and removed after the P pulse. Standard 5 V programmers lack the necessary high-voltage generation and sequencing; attempting programming with insufficient VPP causes incomplete or failed writes with no error indication.
How does the two-line output control (E and G) reduce system power consumption?
When E = VIH, the M27C64A-20F1 enters standby mode drawing only 100 µA - independent of G state. G then selectively enables outputs only when data is actively read, preventing bus contention and eliminating dynamic switching current in deselected devices. This architecture cuts total memory array power by up to 90% compared to single-enable designs.
Is the M27C64A-20F1 RoHS-compliant despite its ceramic package and lead content?
Yes. The FDIP28W package carries ST's ECOPACK® designation, confirming lead-free terminations and compliance with RoHS Directive 2011/65/EU. JEDEC JESD97 marking appears on both package and inner box label; maximum soldering temperature ratings are specified per JEDEC standards - verified in ST's official ECOPACK documentation.
M27C64A-20F1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- 28-CDIP (0.600", 15.24mm) Window
- Packaging:
- Tube
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- EPROM
- Technology:
- EPROM - UV
- Memory Size:
- 64Kbit
- Memory Organization:
- 8K x 8
- Memory Interface:
- Parallel
- Clock Frequency:
- -
- Write Cycle Time - Word, Page:
- -
- Access Time:
- 200 ns
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 28-CDIP Frit Seal with Window
M27C64A-20F1 FAQ
1.How can I place an order for M27C64A-20F1 through Aetrix?
Please submit a Request for Quotation (RFQ) for M27C64A-20F1 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 M27C64A-20F1 reliable?
The price and inventory of M27C64A-20F1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for M27C64A-20F1 is usually 5 days.
3.What payment methods are accepted for M27C64A-20F1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for M27C64A-20F1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for M27C64A-20F1?
M27C64A-20F1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your M27C64A-20F1 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 M27C64A-20F1?
For technical support, including M27C64A-20F1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your M27C64A-20F1 requirements.
6.How does Aetrix verify that M27C64A-20F1 is sourced from the original manufacturer or authorized distributors?
All M27C64A-20F1 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 M27C64A-20F1 meets industry standards.
7.What is the process for return or replacement of M27C64A-20F1?
All M27C64A-20F1 units undergo pre-shipment inspection (PSI). If there is an issue with M27C64A-20F1, 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 M27C64A-20F1 part is unused and in its original packaging.
Return procedure for M27C64A-20F1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
M27C64A-20F1 Tags
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M24C02-WMN6TP
STMicroelectronics
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AT24C02C-XHM-T
Microchip Technology
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AT21CS01-STUM10-T
Microchip Technology
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AT24C02C-SSHM-T
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24LC01BT-I/OT
Microchip Technology
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M24C02-FMC6TG
STMicroelectronics
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AT24CS02-SSHM-T
Microchip Technology
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93LC46BT-I/OT
Microchip Technology
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AT24C04C-SSHM-T
Microchip Technology
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24LC01BT-I/SN
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24AA02UIDT-I/OT
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AT24C08C-STUM-T
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