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STMicroelectronics M27C4001-12B1
- Part No.:
- M27C4001-12B1
- Manufacturer:
- STMicroelectronics
- Category:
- Memory
- Package:
- 32-DIP (0.600", 15.24mm)
- Datasheet:
-
M27C4001-12B1.pdf
- Description:
- IC EPROM 4MBIT PARALLEL 32DIP
- Quantity:
- Payment:
- Shipping:
Inventory:3,836
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Product details
Overview
M27C4001-12B1 from STMicroelectronics is a 4 Mbit (512K × 8) UV-erasable EPROM in a 32-pin PDIP package, operating at 5V ±10%, with 35ns access time and 30mA active current. It features dual-line output control (E and G), electronic signature (20h/41h), and supports programming at 12.75V with 100µs/word pulse width - used in legacy microprocessor boot memory and firmware storage applications.
For engineers reviewing the M27C4001-12B1 datasheet, M27C4001-12B1 pinout, M27C4001-12B1 application, or M27C4001-12B1 equivalent, key selection criteria include UV erasability, TTL-compatible timing, standby current of 100µA, PDIP32 mechanical compatibility, and PRESTO II programming algorithm support.
Technical Context
The M27C4001-12B1 implements a standard NMOS EPROM architecture with address decoding for A0–A18 (524,288 locations), eight bidirectional data I/O lines (Q0–Q7), and two independent enable controls: Chip Enable (E) for power gating and Output Enable (G) for bus contention management. Its logic diagram confirms full TTL-level input compatibility except for VPP and A9 during electronic signature.
Programming requires precise voltage sequencing: VCC = 6.25V ±0.25V and VPP = 12.75V ±0.25V applied simultaneously, with E pulsed low while G held high; verify uses VPP = 12.75V, VCC = 6.25V, E = VIH, G = VIL. Erasure is exclusively UV-based via the quartz window in FDIP variants - not applicable to this PDIP (B-suffix) OTP-capable but UV-incompatible variant.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 4 Mbit (524,288 × 8 bits) - supports full 19-bit addressing for 512KB firmware images |
| Access Time | 35 ns - enables direct interface with 20–25 MHz Z80, 68K, or early x86 CPUs without wait states |
| Supply Voltage (Read) | 5 V ±10% - compatible with standard TTL/CMOS logic rails and legacy board power domains |
| Active Current | 30 mA at 5 MHz - defines thermal load and decoupling requirements (0.1 µF ceramic per device) |
| Standby Current | 100 µA - enables low-power retention in battery-backed systems or idle microcontroller buses |
| Programming Voltage | 12.75 V ±0.25 V - requires dedicated HV supply rail; not derived from VCC |
| Electronic Signature | Manufacturer Code 20h, Device Code 41h - enables automated programmer identification and algorithm selection |
Pinout & Package
Package: PDIP32 (Plastic Dual In-line Package, 600 mil width), ECOPACK®-compliant, lead-free, through-hole mount.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A18 | Address Inputs | 19-bit address bus interface; fully decoded internally to select one of 524,288 bytes |
| Q0–Q7 | Data Outputs / Programming Inputs | Bidirectional 8-bit data path; outputs valid only when E and G are low; accepts parallel data during programming |
| E | Chip Enable | Primary device select; CMOS-high (VIH > VCC − 0.2V) places device in 100 µA standby; TTL-low enables read/program |
| G | Output Enable | Secondary output gate; controls Q0–Q7 Hi-Z vs. driven state independently of E - prevents bus contention in multi-chip arrays |
| VPP | Programming Supply | 12.75 V input required only during programming/verify; must be applied simultaneously with VCC |
| VCC | Power Supply | 5 V ±10% for read; 6.25 V ±0.25% for programming - strict sequencing required relative to VPP |
| VSS | Ground | Reference return for all signals; requires low-inductance connection to minimize noise during fast transitions |
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 on shared data bus |
| PRESTO II programming algorithm | Guarantees cell margin via automatic 100 µs pulse cycling and margin-mode verify - eliminates overprogramming and extends data retention |
| Electronic signature (20h/41h) | Allows programming hardware to auto-detect STMicroelectronics M27C4001 without manual part selection - reduces setup errors |
| ECOPACK® compliance | Lead-free PDIP32 package meeting JEDEC JESD97 marking standards - supports RoHS-compliant legacy system rework |
Applications
| Industrial PLC Firmware Storage | Legacy Medical Device Boot ROM |
|---|---|
Use Scenario: Storing fixed boot code and safety-critical initialization routines in DIN-rail mounted programmable logic controllers. IC Role / Device Role / Timing Role: Non-volatile boot memory mapped to CPU reset vector; accessed at power-on with 35ns tACC to meet tight startup timing budgets. Use Value: UV-erasability allows field firmware updates using certified UV erasers; PDIP32 enables socketed replacement without reflow. | Use Scenario: Holding immutable diagnostic self-test sequences and regulatory-compliant calibration constants in FDA-cleared patient monitors. IC Role / Device Role / Timing Role: Read-only execution memory for 80C188-based controller; operates at 5V with 100µA standby to minimize battery drain during sleep mode. Use Value: Electronic signature (20h/41h) ensures programming tools load correct algorithm - critical for audit-trail integrity in regulated environments. |
| Avionics Maintenance Terminal BIOS | Test Equipment PROM Emulation |
Use Scenario: Providing configuration and diagnostics firmware for portable aircraft maintenance laptops operating in extended temperature ranges. IC Role / Device Role / Timing Role: Standalone EPROM interfaced to ISA-bus-compatible controller; withstands –40°C to +85°C industrial temp grade operation. Use Value: 30mA active current and 35ns access allow real-time register reads during BIT (Built-In Test) without CPU throttling. | Use Scenario: Emulating mask ROM behavior in FPGA-based logic analyzers during hardware validation of legacy digital subsystems. IC Role / Device Role / Timing Role: Pin-compatible drop-in replacement for obsolete 27C4001 variants; supports same address/data/control timing as original design. Use Value: PRESTO II programming enables reliable reprogramming in lab environments - essential for iterative test pattern development. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar EPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AM27C4001-12DC | Same 4 Mbit ×8 organization, 35ns access, but uses AMD's proprietary programming algorithm and signature codes (01h/41h) | Requires AMD-specific programmer firmware; not recognized by ST-optimized tools | Select only if existing toolchain supports AMD signature and timing margins |
| MX27C4001PC-12 | Macronix variant with identical pinout and DC specs, but AC parameters tested under different load conditions (100pF vs. 30pF) | May exhibit marginal timing at 25MHz bus speeds due to longer tGLQV under heavy capacitive loading | Prefer for cost-sensitive replacements where board layout has minimal trace capacitance |
Compared with AM27C4001-12DC and MX27C4001PC-12, the M27C4001-12B1 offers guaranteed PRESTO II margin verification and ST-specific electronic signature - critical for automated programming repeatability and long-term firmware traceability in regulated industries.
Availability
M27C4001-12B1 is available at Aetrix Electronics and suitable for industrial PLC firmware storage, legacy medical device boot ROM, and avionics maintenance terminal BIOS requiring stable component supply across extended product lifecycles.
Supply support for M27C4001-12B1 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, specializing in automotive, industrial, and power discrete solutions with strong heritage in non-volatile memory.
The M27C4001 belongs to ST's legacy EPROM product line, designed specifically for high-reliability, long-lifecycle embedded systems requiring field-upgradable firmware in UV-erasable or OTP configurations.
FAQ
Is M27C4001-12B1 UV-erasable?
No. The "B" suffix denotes PDIP32 packaging, which lacks a quartz window and is OTP-capable only. UV erasure applies solely to FDIP32W (windowed ceramic) variants. This part retains programmed data indefinitely unless physically replaced.
What programming voltage and sequence are required?
VPP must be 12.75 V ±0.25 V and VCC must be 6.25 V ±0.25 V, applied simultaneously before pulsing E low. G must be held high during programming. Failure to meet voltage tolerances or sequencing causes incomplete programming or cell damage.
Can M27C4001-12B1 operate at 3.3V?
No. The device requires 5 V ±10% for read operations and 6.25 V ±0.25 V for programming. It is not 3.3V-tolerant; applying 3.3V to VCC results in undefined output states and failed read cycles per DC characteristics tables.
Does it support common memory bus protocols like ISA or VME?
Yes - its TTL-compatible inputs, dual enable control (E/G), and 35ns timing align with ISA bus specifications for 8-bit memory-mapped peripherals. It does not implement VME arbitration or data transfer protocols but can be interfaced via custom glue logic.
M27C4001-12B1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- 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:
- 120 ns
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 32-PDIP
M27C4001-12B1 FAQ
1.How can I place an order for M27C4001-12B1 through Aetrix?
Please submit a Request for Quotation (RFQ) for M27C4001-12B1 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 M27C4001-12B1 reliable?
The price and inventory of M27C4001-12B1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for M27C4001-12B1 is usually 5 days.
3.What payment methods are accepted for M27C4001-12B1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for M27C4001-12B1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for M27C4001-12B1?
M27C4001-12B1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your M27C4001-12B1 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 M27C4001-12B1?
For technical support, including M27C4001-12B1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your M27C4001-12B1 requirements.
6.How does Aetrix verify that M27C4001-12B1 is sourced from the original manufacturer or authorized distributors?
All M27C4001-12B1 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 M27C4001-12B1 meets industry standards.
7.What is the process for return or replacement of M27C4001-12B1?
All M27C4001-12B1 units undergo pre-shipment inspection (PSI). If there is an issue with M27C4001-12B1, 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 M27C4001-12B1 part is unused and in its original packaging.
Return procedure for M27C4001-12B1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
M27C4001-12B1 Tags
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M24C02-WMN6TP
STMicroelectronics
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AT24C02C-XHM-T
Microchip Technology
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AT21CS01-STUM10-T
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24LC01BT-I/OT
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M24C02-FMC6TG
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AT24CS02-SSHM-T
Microchip Technology
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93LC46BT-I/OT
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AT24C04C-SSHM-T
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24LC01BT-I/SN
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24AA02UIDT-I/OT
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