My Inquiry
My Account
Microchip Technology AT29C040A-90JI
- Part No.:
- AT29C040A-90JI
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 32-LCC (J-Lead)
- Datasheet:
-
AT29C040A-90JI.pdf
- Description:
- IC FLASH 4MBIT PARALLEL 32PLCC
- Quantity:
- Payment:
- Shipping:
Inventory:4,346
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
AT29C040A-90JI from Atmel is a 4-megabit (512K × 8) 5-volt-only Flash memory IC organized in 2048 sectors of 256 bytes each, featuring 90 ns read access time, 10 ms sector program cycle time, and hardware/software data protection. It operates across –40°C to +85°C and supports in-system reprogramming without high-voltage programming signals - used in embedded boot code storage, firmware update modules, and industrial controller firmware retention.
For engineers reviewing the AT29C040A-90JI datasheet, AT29C040A-90JI pinout, AT29C040A-90JI application, or AT29C040A-90JI equivalent, key selection considerations include industrial temperature rating, 256-byte sector architecture, DATA polling and toggle-bit program status detection, boot block lockout capability, and PLCC-32 package compatibility with legacy socketed designs.
Technical Context
The AT29C040A-90JI implements a sector-based Flash architecture where each 256-byte sector is erased and programmed independently using internal address/data latches and an autonomous control timer. Its dual-line chip enable (CE) and output enable (OE) logic enables bus contention avoidance during mixed-read/write operations.
It integrates both hardware-level protection (VCC sense, 5 ms power-on delay, noise filtering on WE/CE) and software-controlled data protection via three-byte unlock sequences. Boot block lockout is implemented for two independent 16K-byte regions - one at lowest addresses (0x00000–0x03FFF), one at highest (0x7C000–0x7FFFF) - enabling secure system boot code preservation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Density | 4 Mbit (524,288 × 8), sufficient for full BIOS/firmware images in legacy embedded systems |
| Read Access Time | 90 ns - enables direct execution from memory in 8-bit microcontroller systems without wait states |
| Sector Size | 256 bytes - allows fine-grained firmware updates without erasing entire device |
| Program Cycle Time | 10 ms per sector - deterministic timing for host firmware scheduling of write operations |
| Operating Voltage | 5 V ±10% - compatible with legacy TTL/CMOS logic rails; no auxiliary voltage required |
| Temperature Range | –40°C to +85°C - qualified for industrial control, automotive body electronics, and outdoor equipment |
| Endurance | >10,000 program/erase cycles per sector - supports field firmware upgrades over multi-year product life |
| Standby Current | 100 µA (CMOS) - enables low-power sleep modes in battery-backed applications |
Pinout & Package
AT29C040A-90JI is packaged in a 32-lead Plastic J-Leaded Chip Carrier (PLCC-32), pin-compatible with industry-standard 32J footprint per JEDEC MS-016 Variation AE. The package features gull-wing leads, 1.27 mm pitch, and a 12.45 mm × 14.95 mm body size - suitable for through-hole and surface-mount socketed designs.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A18 | Address Inputs | 19-bit address bus supporting full 512K-word addressing; A0–A7 select byte within 256-byte sector |
| I/O0–I/O7 | Bidirectional Data Bus | CMOS/TTL-compatible 8-bit data path; I/O7 used for DATA polling, I/O6 for toggle-bit status monitoring |
| CE | Chip Enable | Active-low global enable; when high, places outputs in high-impedance state and inhibits programming |
| OE | Output Enable | Active-low read control; used with CE to prevent bus contention during partial memory accesses |
| WE | Write Enable | Active-low programming control; initiates byte load and sector program cycles when CE is low and OE is high |
| VCC | Power Supply | +5 V ±10% supply; powers core logic and charge pump for internal erase/program operations |
| GND | Ground Reference | Signal and power ground reference for all inputs, outputs, and internal circuitry |
| NC | No Connect | Pin 16 (PLCC top view) is unconnected - must remain floating; not tied to VCC or GND |
Key Features
| Feature | Design Value |
|---|---|
| Single 5V Reprogramming | Eliminates need for +12 V programming supplies - simplifies power design and enables true in-system updates |
| Hardware Data Protection | VCC sense, 5 ms power-on delay, and noise filtering prevent accidental writes during brown-out or EMI events |
| Software Data Protection | Three-byte unlock sequence (AAh/55h/A0h) required before any sector program - prevents unintended firmware corruption |
| Dual Boot Block Lockout | Independent 16K-byte lockout for lower (0x00000) and upper (0x7C000) memory regions - secures boot loader and recovery image |
| DATA Polling & Toggle Bit | Real-time program status feedback via I/O7 complement or I/O6 toggling - enables interrupt-driven write completion handling |
Applications
| Industrial PLC Firmware Storage | Legacy PC BIOS Retention |
|---|---|
Use Scenario: Storing configuration logic and motion control algorithms in programmable logic controllers deployed in factory automation environments. IC Role / Device Role / Timing Role: Nonvolatile firmware storage with sector-level update capability and industrial temperature resilience. Use Value: Enables field-upgradable ladder logic without replacing hardware; boot block lockout preserves critical startup routines during updates. | Use Scenario: Retaining BIOS code in legacy x86-based industrial PCs and embedded motherboards requiring socketed Flash replacement. IC Role / Device Role / Timing Role: Pin-compatible EPROM replacement with in-system reprogrammability and 90 ns read speed. Use Value: Eliminates need for UV-erasable EPROM programmers; supports BIOS patching via standard ISA/PCI interface without board removal. |
| Medical Device Boot Loader | Telecom Line Card Configuration |
Use Scenario: Securing boot code for FDA-cleared diagnostic instruments where firmware integrity is safety-critical. IC Role / Device Role / Timing Role: Dual-boot-block protected storage for primary and fallback boot loaders. Use Value: Prevents unauthorized modification of startup code; software/hardware protection layers satisfy IEC 62304 traceability requirements. | Use Scenario: Storing line-specific initialization parameters and DSP configuration tables in telecom access equipment. IC Role / Device Role / Timing Role: Sector-erasable nonvolatile memory supporting hot-swap configuration updates without service interruption. Use Value: Allows per-line firmware tuning via 256-byte sector writes; DATA polling ensures deterministic update completion for SNMP-managed devices. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Flash memory applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AM29LV040B-90JC | 4 Mbit, 90 ns, 3.3 V core (5 V I/O tolerant); requires VPP = 12 V for sector erase | Not 5 V–only; incompatible with pure 5 V systems lacking VPP generation | Select only if migrating to lower-power 3.3 V design with VPP support |
| SST39VF040-90-4C-NHE | 4 Mbit, 90 ns, 3.3 V operation; no VPP required but lacks boot block lockout | Requires level-shifting in 5 V systems; no hardware-enforced boot code protection | Prefer for new 3.3 V designs where boot security is managed in software |
Compared with AM29LV040B-90JC and SST39VF040-90-4C-NHE, the AT29C040A-90JI uniquely delivers true 5 V–only operation with integrated boot block lockout and hardware VCC-sense protection - making it the only drop-in replacement for legacy 5 V socketed Flash designs requiring robust in-field update security.
Availability
AT29C040A-90JI is available at Aetrix Electronics and suitable for industrial PLC firmware storage, legacy PC BIOS retention, medical device boot loader implementation, and telecom line card configuration requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for AT29C040A-90JI 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 (now part of Microchip Technology) is a semiconductor manufacturer specializing in microcontrollers, Flash memory, and secure authentication ICs for industrial, automotive, and consumer applications.
The AT29C040A-90JI belongs to Atmel's 5-volt-only Flash family designed specifically for socketed, in-system reprogrammable firmware storage in legacy 5 V embedded systems - emphasizing reliability, sector granularity, and hardware-enforced data integrity.
FAQ
What is the operating temperature range of the AT29C040A-90JI?
The AT29C040A-90JI is rated for industrial temperature operation from –40°C to +85°C. This specification is confirmed in the Ordering Information table (page 13) and applies specifically to the "-JI" suffix variant. The device maintains full functionality-including 90 ns read access, 10 ms sector programming, and DATA polling-across this full range, making it suitable for deployment in harsh environments such as factory floors, outdoor telecom cabinets, and vehicle-mounted control units.
Does the AT29C040A-90JI require high-voltage programming signals?
No, the AT29C040A-90JI does not require high-voltage programming signals. As stated in the Features section and Device Operation description, it is a "5-volt only" Flash memory: all programming, erasing, and reading functions operate solely from the VCC supply (5 V ±10%). Internal charge pumps generate necessary high voltages, eliminating the need for external VPP pins or 12 V supplies - a key differentiator from earlier EPROM or UV-erasable Flash devices.
How is program completion detected on the AT29C040A-90JI?
Program completion on the AT29C040A-90JI is detected using either DATA polling on I/O7 or the toggle-bit method on I/O6. During programming, reading the last loaded byte returns the complement of the data on I/O7; when complete, true data appears. Alternatively, I/O6 toggles between 0 and 1 until completion, then stabilizes. Both methods are specified in the AC Characteristics tables (pages 11–12) and supported across the full –40°C to +85°C range of the AT29C040A-90JI.
What package type is used for the AT29C040A-90JI?
The AT29C040A-90JI uses a 32-lead Plastic J-Leaded Chip Carrier (PLCC-32), designated as package code "32J" in the Ordering Information table (page 13). Its mechanical dimensions conform to JEDEC MS-016 Variation AE, with a 12.45 mm × 14.95 mm body and 1.27 mm lead pitch. This package supports both socketed and surface-mount assembly and is pin-identical to other AT29C040A variants with the "-J" suffix.
Can the AT29C040A-90JI be used as a direct replacement for EPROMs like the 27C040?
Yes, the AT29C040A-90JI is functionally and pin-compatible with the 27C040 EPROM in read mode (CE/OE/WE logic matches standard EPROM timing), but adds in-system reprogrammability without UV erasure. Unlike the 27C040, it requires specific software command sequences for programming and supports sector erase. Its 90 ns access time and 5 V operation make it a drop-in read replacement; however, write operations require updated host firmware to issue unlock sequences and manage DATA polling - confirmed in the Device Operation and Software Data Protection sections.
AT29C040A-90JI Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 32-LCC (J-Lead)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- FLASH
- Technology:
- FLASH
- Memory Size:
- 4Mbit
- Memory Organization:
- 512K x 8
- Memory Interface:
- Parallel
- Clock Frequency:
- -
- Write Cycle Time - Word, Page:
- 10ms
- Access Time:
- 90 ns
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- -40°C ~ 85°C (TC)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 32-PLCC (13.97x11.43)
AT29C040A-90JI FAQ
1.How can I place an order for AT29C040A-90JI through Aetrix?
Please submit a Request for Quotation (RFQ) for AT29C040A-90JI 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 AT29C040A-90JI reliable?
The price and inventory of AT29C040A-90JI are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT29C040A-90JI is usually 5 days.
3.What payment methods are accepted for AT29C040A-90JI?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT29C040A-90JI transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT29C040A-90JI?
AT29C040A-90JI orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT29C040A-90JI 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 AT29C040A-90JI?
For technical support, including AT29C040A-90JI datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT29C040A-90JI requirements.
6.How does Aetrix verify that AT29C040A-90JI is sourced from the original manufacturer or authorized distributors?
All AT29C040A-90JI 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 AT29C040A-90JI meets industry standards.
7.What is the process for return or replacement of AT29C040A-90JI?
All AT29C040A-90JI units undergo pre-shipment inspection (PSI). If there is an issue with AT29C040A-90JI, 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 AT29C040A-90JI part is unused and in its original packaging.
Return procedure for AT29C040A-90JI:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AT29C040A-90JI Tags
-
M24C02-WMN6TP
STMicroelectronics
-
AT24C02C-XHM-T
Microchip Technology
-
AT21CS01-STUM10-T
Microchip Technology
-
AT24C02C-SSHM-T
Microchip Technology
-
24LC01BT-I/OT
Microchip Technology
-
M24C02-FMC6TG
STMicroelectronics
-
AT24CS02-SSHM-T
Microchip Technology
-
93LC46BT-I/OT
Microchip Technology
-
AT24C04C-SSHM-T
Microchip Technology
-
24LC01BT-I/SN
Microchip Technology
-
24AA02UIDT-I/OT
Microchip Technology
-
AT24C08C-STUM-T
Microchip Technology
Tech Hub
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
