25AA040AT-I/OT Microchip Integrated Circuit (SOT23 (6-Pin)) In Stock

25AA040AT-I/OT is a 4 Kbit SPI serial EEPROM by Microchip, organized as 512 x 8 bits. Key specs: 1.8 V supply, 10 MHz SPI clock, 200-year data retention in SOT-23-6 package. From $0.35, in stock with worldwide shipping.

ACTIVEIntegrated CircuitVerified Jul 2026
Package / Visual Reference
25AA040AT-I/OTSOT23 (6-Pin)
Quick Facts
Manufacturer
Microchip
Package
SOT23 (6-Pin)
Pin Count
6
Lifecycle
ACTIVE
Category
Integrated Circuit
Price
From $0.2400(MOQ 1)
Temp Range
-40.0°C to 85.0°C
RoHS
Compliant
Lead Time
3–7 business days
Shipping
DHL Express · Worldwide

Key Features

  • 4 Kbit (512 x 8) SPI EEPROM with 10 MHz clock and 1.8 V minimum supply for ultra-low-voltage microcontroller systems
  • 1,000,000 write/erase cycle endurance and 200-year data retention ensuring long-term reliability in industrial and consumer applications
  • SOT-23-6 package with only 3 signal pins (CS, SCK, SI/SO) minimizes PCB footprint for compact, space-constrained designs

Applications

25AA040AT-I/OT is used in wearable medical devices, smart meters, and battery-powered IoT nodes that need non-volatile configuration or calibration storage at 1.8 V. Its 10 MHz SPI interface lets a host MCU read or write the full 512-byte array in under 1 ms, minimizing the time spent with the SPI bus active. The SOT-23-6 package and 200-year retention make it a reliable choice for parameter storage in industrial sensors with decade-long field lifetimes.

Specifications

Pbfree CodeYes
Manufacturer Package CodeSOT-23-6
Factory Lead Time6Weeks
YTEOL8
Clock Frequency-Max (fCLK)10MHz
Data Retention Time-Min200
Endurance1000000 Write/Erase Cycles
JESD-30 CodeR-PDSO-G6
JESD-609 Codee3
Memory Density4096bit
Memory IC TypeEEPROM
Memory Width8
Number of Functions1
Number of Ports1
Number of Words512words
Number of Words Code512
Operating ModeSYNCHRONOUS
Organization512X8
Output Characteristics3-STATE
Package Body MaterialPLASTIC/EPOXY
Package Equivalence CodeTSOP6,.11,37
Package ShapeRECTANGULAR
Package StyleSMALL OUTLINE, LOW PROFILE, SHRINK PITCH
Parallel/SerialSERIAL
Peak Reflow Temperature (Cel)260
Programming Voltage5V
Qualification StatusNot Qualified
Serial Bus TypeSPI
Standby Current-Max0.000001A
Supply Current-Max0.005mA
Supply Voltage-Max (Vsup)5.5V
Supply Voltage-Min (Vsup)1.8V
Supply Voltage-Nom (Vsup)5V
Surface MountYES
TechnologyCMOS
Temperature GradeINDUSTRIAL
Terminal FinishMatte Tin (Sn)
Terminal FormGULL WING
Terminal Pitch0.95mm
Terminal PositionDUAL
Write Cycle Time-Max (tWC)5ms
Write ProtectionHARDWARE/SOFTWARE
PackageSOT23 (6-Pin)

Compliance & Regulatory

RoHS StatusCompliant
Lead-FreeYes (Pb-Free)
Moisture Sensitivity LevelMSL 1
ECCNEAR99
HTS Code8542.32.00.51
Country of OriginThailand

Datasheet

25AA040AT-I/OT Datasheet Download

Official datasheet from Microchip

Alternate & Equivalent Parts

No known alternates. Submit an RFQ and our team can suggest alternatives.

Frequently Asked Questions

How long can 25AA040AT-I/OT retain stored data, and how many write cycles does it support?

The 25AA040AT-I/OT is specified for a minimum data retention of 200 years and endures up to 1,000,000 write/erase cycles per byte. This combination of high endurance and long retention makes it suitable for configuration data that is written infrequently but must survive the entire product lifetime in field deployments.

At what supply voltage and SPI clock speed does 25AA040AT-I/OT operate, and why does that matter for low-power designs?

The device operates from 1.8 V to 5.5 V and supports SPI clock rates up to 10 MHz at 1.8 V. This 1.8 V minimum supply means it can share the same power rail as low-voltage MCUs like PIC16LF or MSP430 series without a level shifter, reducing bill-of-materials cost and quiescent current by eliminating voltage translation.

When is the 4 Kbit density of 25AA040AT-I/OT sufficient compared to a larger 64 Kbit EEPROM for a sensor calibration use case?

For a sensor with 8 to 16 calibration coefficients stored as 16-bit values, 4 Kbit provides 512 bytes—enough for 128 calibration words plus factory serial number and firmware version. Choosing 4 Kbit over a 64 Kbit device reduces cost by roughly 50% and keeps the SOT-23-6 footprint under 3 mm², which is important for miniaturized probes and wearable patches.

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AvailabilityIn Stock
Reference Price (USD)
From $0.2400
Buy from 1pc · Factory-direct pricing
Qty.Unit PriceExt. Price
1+$0.5500$0.55
5+$0.5060$2.53
10+$0.4840$4.84
100+$0.4700$47.00
1000+$0.4500$450.00
3000+$0.2400$720.00
pcs
Unit price: $0.5500 · Total: $0.55

In Stock · 24h Response · Worldwide Shipping

Lead Time3-7 business days
MOQFrom 1 piece
ShippingDHL / FedEx / UPS
OriginChina (Authorized)

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Thomas Mueller
Hardware Lead, SensorTech GmbH, Germany