24CW640T-I/OT - 64Kbit I2C EEPROM, SOT-23-5 | Microchip
Référence : 24CW640T-I/OT ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $0.72 | $0,72 |
| 10 | $0.65 | $6,50 |
| 100 | $0.56 | $56,00 |
| 500 | $0.48 | $240,00 |
| 1 000 | $0.42 | $420,00 |
| 3 000 | $0.36 | $1 080,00 |
24CW640T-I/OT Présentation
A serial EEPROM (Electrically Erasable Programmable Read-Only Memory) is a type of non-volatile memory that retains data without power and allows individual byte-level electrical reprogramming through a simple two-wire serial interface. Within the semiconductor memory hierarchy, EEPROM sits between one-time-programmable ROM and higher-density Flash, offering superior endurance and per-byte write granularity at the cost of lower density. The 24CW Series is positioned by Microchip as a low-power, low-cost, I2C-compatible EEPROM family optimized for consumer and industrial parameter storage.
Key differentiating features of the 24CW640 include 64-Kbit density in the industry-standard 64-Kbit I2C EEPROM footprint, software-configurable write protection for upper half or full array, a dedicated WP pin for hardware protection, and Schmitt-triggered inputs for noise-tolerant bus operation. The wide 1.6 V to 5.5 V operating range allows direct connection to 1.8 V, 2.5 V, 3.3 V, or 5 V microcontroller I/O rails without level translation.
Internally, the 24CW640 uses a CMOS floating-gate process with on-chip charge pump for byte-level programming and an integrated RC oscillator for write-cycle timing. The device supports standard, fast, and fast-plus I2C speeds (100 kHz, 400 kHz, and 1 MHz respectively), and its 450 ns access time provides fast read throughput for polling-based firmware designs. Page writes of up to 16 bytes maximize bus efficiency for parameter-table updates.
Typical applications include consumer-electronics configuration storage, industrial sensor calibration data retention, IoT edge-node parameter logging, audio/video equipment user settings, and any battery-backed or power-cycled system that requires reliable non-volatile storage of small data sets. The SOT-23-5 package makes it well suited for space-constrained PCB designs.
When designing with this part, place a 100 nF decoupling capacitor close to the VCC pin and observe I2C bus pull-up sizing (typically 2.2 k to 10 k depending on speed and bus capacitance). The WP pin must be tied to VCC or GND; leaving it floating can cause unreliable write-protect behavior. For page-write operations, ensure firmware respects the 16-byte page boundary to avoid wrap-around writes.
This page synthesizes distributor pricing, drop-in I2C EEPROM alternatives, and practical design notes not aggregated on any single manufacturer or distributor page.
Alternatives de remplacement direct pour 24CW640T-I/OT — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
24CW640T-I/MNY
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
24CW640T-I/OT Spécifications
| Type de mémoire | Non-Volatile EEPROM |
| Taille de mémoire | 64 Kbit (8,192 x 8) |
| Organisation de la mémoire | 8 K x 8 bytes |
| Interface | I2C (2-wire serial) |
| Fréquence d'horloge maximale | 1 MHz (Fast-Plus) |
| Access Time | 450 ns |
| Tension d'alimentation | 1.6 V to 5.5 V |
| Write Protection | Software + Hardware WP pin |
| Page Size | 16 bytes |
| Endurance | 1,000,000 erase/write cycles per byte |
| Data Retention | 200 years |
| Température de fonctionnement | -40 C to +85 C (Industrial) |
| Boîtier | SOT-23-5 (5-pin) |
| Type de montage | Surface Mount |
| Standard Pack Quantity | 3,000 (Tape & Reel) |
| Statut RoHS | Compliant |
Configuration des broches de 24CW640T-I/OT
| Broche 1 | SCL — Serial clock input (I2C) |
| Broche 2 | GND — Ground |
| Broche 3 | SDA — Serial data input/output (I2C) |
| Broche 4 | WP — Write protect (tie to VCC for writes, GND to protect) |
| Broche 5 | VCC — Supply voltage (1.6 V to 5.5 V) |
Applications typiques
24CW640T-I/OT convient pour 7 applications: IoT Edge Sensor Calibration Storage, Consumer Audio Equipment User Settings, Industrial Control Module Parameter Backup, Smart Home Hub Device Pairing Memory, Medical Device Calibration Log Retention, Automotive Infotainment Preset Storage, LED Display Module Configuration Memory.
IoT Edge Sensor Calibration Storage
The 24CW640T-I/OT stores per-unit sensor calibration coefficients, factory-trim values, and runtime configuration parameters in wireless IoT edge nodes where the 1.6 V minimum supply enables direct connection to coin-cell or Li-ion depleted batteries down to 1.8 V rails. The 8 Kbyte array is well sized for storing 16-bit calibration tables for temperature, humidity, and gas sensors, while the 1 million erase/write cycle endurance supports daily re-calibration over a 10-year product lifetime. Designers place the part on the I2C bus alongside a low-power MCU; the WP pin is tied to a GPIO to allow firmware-controlled write protection once calibration is finalized in production.
Recommandé
Consumer Audio Equipment User Settings
The 24CW640T-I/OT stores user preferences such as volume, EQ curves, input selections, and last-played track metadata in audio amplifiers, soundbars, and Bluetooth speakers. Its 450 ns access time ensures fast read latency when the MCU reads settings at boot, and the 1 MHz I2C clock minimizes bus time during page writes of multi-byte EQ profiles. The wide 1.6 V to 5.5 V supply allows direct connection to 1.8 V audio DSP rails or 5 V legacy amplifier logic without level translation. Hardware WP is tied to a chassis-detect GPIO to prevent firmware re-flashing of factory-tuned audio profiles.
Recommandé
Industrial Control Module Parameter Backup
The 24CW640T-I/OT retains PLC module configuration, Modbus node addresses, and last-known-good process parameters in industrial automation systems where -40 C to +85 C operation and 200-year data retention are mandatory. Its 8 Kbyte capacity easily stores ladder-logic tag maps and PID tuning constants, while the 1 million cycle endurance supports frequent parameter updates from HMI panels. The SOT-23-5 package fits the small footprint of distributed I/O modules, and the software write-protect opcodes allow field engineers to lock critical calibration data against accidental overwrites during commissioning.
Recommandé
Smart Home Hub Device Pairing Memory
The 24CW640T-I/OT stores Zigbee/Z-Wave/Wi-Fi device pairing tables, encryption keys, and room-assignment metadata in smart-home hubs and bridges. Its 8 Kbyte array accommodates approximately 50 paired-device records with 128-bit UUIDs plus friendly names, and the wide voltage range simplifies multi-rail designs where the hub runs from 3.3 V logic and 5 V radio rails. Fast-Plus 1 MHz I2C allows rapid lookup during device-discovery bursts without slowing the main processor. Hardware WP protects security keys while software block protect can lock the device table separately.
Recommandé
Medical Device Calibration Log Retention
The 24CW640T-I/OT provides non-volatile retention of calibration date, technician ID, and measurement-traceability data in portable medical devices such as blood-pressure monitors, pulse oximeters, and glucose meters. The 1.6 V minimum supply is critical for single-AAA-cell designs operating down to 0.9 V via a boost converter, and the 200-year data retention exceeds the 10-year service life of most medical disposables. The SOT-23-5 footprint fits inside miniaturized wearables, and the 1 million cycle endurance supports daily self-test logging throughout the device lifetime.
Recommandé
Automotive Infotainment Preset Storage
The 24CW640T-I/OT is used in non-safety automotive infotainment systems to store radio presets, seat/mirror positions, climate-control favorites, and last-used navigation destinations across key-off power cycles. Its wide operating temperature range supports under-dash thermal environments, and the wide 1.6 V to 5.5 V supply tolerates load-dump transients when paired with proper input protection. The 8 Kbyte array is sufficient for hundreds of user preferences, and the I2C interface shares the bus with the head-unit MCU. Hardware WP tied to ignition prevents writes while driving per automotive usability guidelines.
Recommandé
LED Display Module Configuration Memory
The 24CW640T-I/OT stores per-module gamma tables, color-calibration coefficients, and address-IDs in daisy-chained LED display panels for digital signage and stadium scoreboards. Its 8 Kbyte capacity holds 256-point gamma curves for three color channels, and the Fast-Plus 1 MHz I2C clock keeps configuration-load time minimal during boot of multi-square-meter displays. The wide 1.6 V to 5.5 V supply matches common 3.3 V and 5 V LED-driver rails, and the SOT-23-5 footprint fits the dense PCB pitch between LED driver ICs in fine-pitch displays.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour 24CW640T-I/OT — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | 24CW640T-I/MNY | 24AA64T-E/MS |
|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | SOT-23-5 | SOT-23-5 | MSOP-8 |
| Memory Size | 64 Kbit (8 K x 8) | 64 Kbit (8 K x 8) | 64 Kbit (8 K x 8) |
| Interface | I2C up to 1 MHz | I2C up to 1 MHz | I2C up to 400 kHz |
| Supply Voltage | 1.6 V to 5.5 V | 1.6 V to 5.5 V | 1.7 V to 5.5 V |
| Write Protection | Software + Hardware WP | Software + Hardware WP | Hardware WP only |
| Endurance | 1M cycles/byte | 1M cycles/byte | 1M cycles/byte |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +125 C (Extended) |
Principaux différenciateurs
- Wide 1.6 V minimum supply enables single-cell battery designs (vs AT24C64 (2.5 V minimum))
- Software-configurable block write protection (vs 24LC64 (hardware WP only))
- Fast-Plus 1 MHz I2C support (vs M24C64 (400 kHz maximum))
Notes de conception
Place a 100 nF ceramic decoupling capacitor within 3 mm of the VCC pin (pin 5) to suppress I2C-bus-induced supply noise. The 24CW640 draws up to 3 mA during write cycles, so the capacitor must supply instantaneous charge without significant VCC droop. For 3.3 V systems sharing the bus with other I2C devices, a bulk 1 uF to 10 uF capacitor near the EEPROM is recommended to maintain bus integrity during multi-device simultaneous writes.
Route the SDA and SCL traces as a differential pair with matched lengths and keep them short (< 50 mm when possible) to minimize capacitive loading and reflections at 1 MHz Fast-Plus speeds. Per Microchip's I2C bus layout guidelines, avoid routing I2C signals parallel to high-frequency switching nodes such as DC-DC converter SW pins or clock oscillator traces. Place 2.2 k to 4.7 k pull-up resistors to VCC; if multiple devices share the bus, calculate the combined pull-up using Rp(min) and Rp(max) formulas from UM10204.
Always tie the WP pin (pin 4) either to VCC or GND - leaving it floating can cause unreliable write-protect behavior and intermittent write failures. Do not exceed 16 bytes in a single page write; writes that cross a page boundary will wrap around and overwrite the start of the current page. After a write command, poll the ACK polling method (send the device address) rather than using a fixed 5 ms delay to maximize write throughput. Ensure the I2C address matches the part variant - the 24CW640 uses address 0x50 (1010_000x) for the standard variant.
Informations de conformité
RoHS and REACH compliant per Microchip product page; lead-free SOT-23-5 package. Not AEC-Q100 qualified - select an automotive-grade EEPROM variant for AEC-Q100 applications.
