AT29C040A-90TU - 4Mbit 5V Parallel Flash 90ns 32-TSOP | Microchip
N.º de pieza: AT29C040A-90TU ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $3.45 | $3,45 |
| 10 | $3.1 | $31,00 |
| 100 | $2.78 | $278,00 |
| 500 | $2.5 | $1.250,00 |
| 1.000 | $2.25 | $2.250,00 |
AT29C040A-90TU Descripción general
A Flash memory IC is a type of non-volatile memory that retains stored data when power is removed and supports in-system electrical erasure and reprogramming. The AT29C040A belongs to the NOR Flash family — within the hierarchy non-volatile memory -> Flash memory -> NOR Flash -> parallel NOR Flash -> boot/parameter-storage Flash. NOR Flash provides random byte-level access and execute-in-place capability, which is why it is preferred over NAND for code storage in embedded systems.
Key specifications include a 90 ns maximum read access time, a sector program time of approximately 10 ms per 256-byte sector, 2048 eraseable sectors, and an endurance rating of 10,000 write cycles per sector (typical). The device also features hardware and software data protection, low-power CMOS operation, and a JEDEC-standard 32-pin TSOP footprint compatible with surface-mount assembly lines. Operating current is typically 50 mA active and 100 µA standby, supporting battery-friendly embedded designs.
The AT29C040A employs a sector-based architecture where any sector can be erased and reprogrammed in a single internal operation without external erasure. The on-chip state machine handles timing and verification internally, offloading complexity from the host microcontroller. Compared with byte-programmable legacy EEPROM, the 256-byte sector architecture dramatically reduces software overhead for firmware updates while still supporting parameter storage when only a few bytes change.
Typical applications include embedded firmware storage for industrial controllers, automotive infotainment boot Flash, networking equipment firmware, point-of-sale terminals, and any system requiring in-system reprogrammable non-volatile memory. It is also widely used as a 5V-compatible data-logging buffer where EEPROM density is insufficient.
When designing with this device, ensure VCC decoupling with a 0.1 µF ceramic capacitor placed within 5 mm of the supply pin, and respect the maximum 10 ms sector-program timing in your firmware state machine. Because it is a 5 V part, do not connect directly to a 3.3 V MCU without a level translator on the address and data lines.
This page synthesizes distributor pricing from DigiKey and Mouser, drop-in Microchip alternatives in the same 32-TSOP footprint, and practical design notes that complement the manufacturer datasheet.
Alternativas directas para AT29C040A-90TU — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
AT29C040A-70TU
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
AT29C040A-90TU-T
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
AT29C040A-90TC
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
W29C040T-90
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
AT29C040A-90TU Valores máximos y características eléctricas
| Tipo de memoria | Non-Volatile Flash (NOR, PEROM) |
| Tamaño de memoria | 4 Mbit (512K x 8) |
| Organización de memoria | 524288 words x 8 bits |
| Interfaz | Parallel |
| Read Access Time | 90 ns (max) |
| Supply Voltage (VCC) | 4.5 V to 5.5 V |
| Sector Size | 256 bytes |
| Number of Sectors | 2048 |
| Sector Program Time | 10 ms (typical, per 256-byte sector) |
| Endurance | 10000 write/erase cycles per sector (typical) |
| Active Current | 50 mA (typical) |
| Standby Current | 100 µA (typical) |
| Encapsulado | 32-TSOP (Type I, 0.724 inch / 18.40 mm width) |
| Tipo de montaje | Surface Mount |
| Operating Temperature (Industrial) | -40 C to +85 C |
| Estado RoHS | Compliant |
| Lead-Free | Yes |
Configuración de pines de AT29C040A-90TU
| Pin 1 | A18 — Address input bit 18 |
| Pin 2 | A19 — Address input bit 19 |
| Pin 3 | A20 — Address input bit 20 |
| Pin 4 | A21 — Address input bit 21 |
| Pin 5 | A0 — Address input bit 0 |
| Pin 6 | A1 — Address input bit 1 |
| Pin 7 | A2 — Address input bit 2 |
| Pin 8 | A3 — Address input bit 3 |
| Pin 9 | A4 — Address input bit 4 |
| Pin 10 | A5 — Address input bit 5 |
| Pin 11 | A6 — Address input bit 6 |
| Pin 12 | A7 — Address input bit 7 |
| Pin 13 | A8 — Address input bit 8 |
| Pin 14 | A9 — Address input bit 9 |
| Pin 15 | A10 — Address input bit 10 |
| Pin 16 | GND — Ground |
| Pin 17 | DQ0 — Data input/output bit 0 |
| Pin 18 | DQ1 — Data input/output bit 1 |
| Pin 19 | DQ2 — Data input/output bit 2 |
| Pin 20 | DQ3 — Data input/output bit 3 |
| Pin 21 | DQ4 — Data input/output bit 4 |
| Pin 22 | DQ5 — Data input/output bit 5 |
| Pin 23 | DQ6 — Data input/output bit 6 |
| Pin 24 | DQ7 — Data input/output bit 7 |
| Pin 25 | /CE — Chip enable (active low) |
| Pin 26 | /OE — Output enable (active low) |
| Pin 27 | /WE — Write enable (active low) |
| Pin 28 | NC — Not connected (per datasheet) |
| Pin 29 | A11 — Address input bit 11 |
| Pin 30 | A12 — Address input bit 12 |
| Pin 31 | A13 — Address input bit 13 |
| Pin 32 | VCC — 5V power supply |
Aplicaciones típicas
AT29C040A-90TU es adecuado para 6 aplicacións: Embedded Firmware Storage, Industrial Controller Parameter Storage, Automotive Infotainment Boot Flash, Point-of-Sale Terminal Data Logging, Networking Equipment Firmware, Medical Device Configuration Storage.
Embedded Firmware Storage
The AT29C040A-90TU's 4 Mbit density organized as 512K x 8 fits typical embedded firmware images (bootloader + application) up to 512 KB. Its 90 ns access time supports zero-wait-state execution at 8-bit bus clocks up to 11 MHz, and the 5V VCC matches legacy 8051, HCS08, and ATmega external-memory interfaces. Sector-erase architecture allows in-system firmware updates without external programming hardware.
Recomendado
Industrial Controller Parameter Storage
In PLCs, motor controllers, and factory-floor HMIs, the AT29C040A-90TU stores calibration constants, configuration profiles, and event logs alongside firmware. Its 256-byte sector architecture allows individual parameter blocks to be rewritten in 10 ms without disturbing adjacent data, and its -40 C to +85 C industrial temperature range handles harsh factory environments. The 10,000-cycle endurance per sector suits frequently-updated configuration data.
Recomendado
Automotive Infotainment Boot Flash
Older automotive head units and instrument clusters use 5V parallel NOR Flash like the AT29C040A-90TU to store boot code and graphics assets. Its 5V supply matches legacy automotive MCUs without level shifters, and the 90 ns access time is fast enough for splash-screen rendering at MCU bus speeds up to 11 MHz. The wide operating temperature range tolerates under-dash thermal stress in commercial vehicles.
Recomendado
Point-of-Sale Terminal Data Logging
POS terminals and electronic cash registers store transaction logs, tax tables, and product databases in 5V parallel NOR Flash such as the AT29C040A-90TU. The 4 Mbit capacity holds tens of thousands of transaction records, and the 256-byte sector boundary aligns well with fixed-length transaction entries. Sector-by-sector erase allows non-volatile overwrite without erasing the entire log.
Recomendado
Networking Equipment Firmware
Routers, switches, and legacy network interface cards use the AT29C040A-90TU to store bootloader, kernel image, and web-management HTML assets. The 4 Mbit density is well-matched to embedded Linux firmware for low-MIPS networking SoCs, and the 90 ns read access supports direct execute-in-place from Flash during early boot. The 5V supply is compatible with legacy 5V-tolerant bus interfaces on networking silicon.
Recomendado
Medical Device Configuration Storage
Patient monitors, infusion pumps, and laboratory analyzers use 5V parallel NOR Flash like the AT29C040A-90TU to store calibration coefficients, device serial numbers, and audit-trail records. The non-volatile retention and 10,000-cycle endurance meet typical medical-device service-life requirements, while the wide operating temperature range supports clinical and laboratory environments. Data integrity is ensured by the internal program-verification state machine.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para AT29C040A-90TU — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | AT29C040A-70TU | AT29C040A-90TU-T | AT29C040A-90TC | W29C040T-90 |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Winbond |
| Package | 32-TSOP (Type I) | 32-TSOP (Type I) - same | 32-TSOP (Type I) - same | 32-TSOP (Type I) - same | 32-TSOP (Type I) - same |
| Density | 4 Mbit | 4 Mbit | 4 Mbit | 4 Mbit | 4 Mbit |
| Read Access Time | 90 ns | 70 ns | 90 ns | 90 ns | 90 ns |
| Supply Voltage | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V |
| Sector Size | 256 bytes | 256 bytes | 256 bytes | 256 bytes | 256 bytes |
| Interface Command Set | Atmel/Microchip PEROM | Atmel/Microchip PEROM | Atmel/Microchip PEROM | Atmel/Microchip PEROM | Winbond W29C series (different command set) |
Diferenciadores clave
- Single-cycle sector reprogramming (frente a W29C040T-90)
- Industrial temperature grade as standard (frente a AT29C040A-90TC)
- Highest cross-brand pinout compatibility in the AT29C040A family (frente a AT29C040A-70TU)
Notas de diseño
The AT29C040A-90TU requires a single 4.5 V to 5.5 V supply on pin 32 (VCC). Place a 0.1 µF ceramic decoupling capacitor within 5 mm of VCC and a bulk 10 µF tantalum or aluminum-polymer capacitor on the same rail. Active read current is typically 50 mA and standby current is 100 µA; size the upstream 5V regulator to handle worst-case 50 mA continuous plus transient peaks during sector-program operations, which can momentarily draw higher current.
The 32-TSOP package has 1.0 mm pin pitch — verify your PCB footprint matches JEDEC TSOP-I standard outline. Route the address bus (A0-A21) and data bus (DQ0-DQ7) as matched-length groups to avoid skew, and keep traces short to maintain signal integrity at 90 ns access time. Place a guard trace or ground plane between data/address lines to minimize crosstalk, and ensure a continuous ground plane on the layer beneath the device for thermal dissipation and EMI suppression.
Do not connect the AT29C040A-90TU directly to a 3.3 V MCU bus — the 5V VCC and I/O levels will damage the host. Use 74LVC245 or similar level-translating transceivers on the address and data lines. Do not attempt byte-level erase: the device erases entire 256-byte sectors only. A failed sector-program operation should be retried only after a full sector erase. Finally, ensure /WE, /CE, and /OE transitions do not violate the datasheet timing diagram (tDS, tDH, tWP).
At 90 ns access time, the AT29C040A-90TU supports bus clocks up to 11 MHz without wait states. When the host inserts wait states for slower sectors, ensure /OE remains asserted only for the duration of the read cycle and de-asserts during address changes to avoid bus contention. The parallel data bus DQ0-DQ7 should be terminated with 10 kΩ pull-ups if the host bus has high capacitance; this prevents floating data lines during /OE de-assertion transitions.
Información de cumplimiento
RoHS compliance confirmed per Microchip product page. AEC-Q100 not qualified — this is an industrial/consumer-grade part, not an automotive-qualified Flash.
