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Home > Products > Integrated Circuits (ICs) > Memory > Memory

Microchip Technology 24LC128-E/SM

Name: 24LC128-E/SM
Brand: Microchip Technology
SKU: 24LC128-E/SM
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: 24LC128-E/SM

Manufacturer:: Microchip Technology

Category:: Memory

Package:: 8-SOIC (0.209", 5.30mm Width)

Datasheet:: 24LC128-E/SM.pdf

Description:: IC EEPROM 128KBIT I2C 8SOIJ

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Product details

Overview

24LC128-E/SM from Microchip Technology Inc. is a 128 Kbit (16K × 8) I²C-compatible serial EEPROM designed for nonvolatile data storage in low-power embedded systems. It operates from 2.5V to 5.5V, supports up to 400 kHz I²C clock frequency, features hardware write-protection via the WP pin, and delivers 1 million erase/write cycles with >200 years data retention. It is used in industrial sensor calibration, power meter configuration, and firmware parameter storage.

For engineers reviewing the 24LC128-E/SM datasheet, 24LC128-E/SM pinout, 24LC128-E/SM application, or 24LC128-E/SM equivalent, key selection criteria include its extended temperature range (–40°C to +125°C), 8-lead SOIC package (SM), 64-byte page write buffer, Schmitt-trigger inputs for noise immunity, and cascading support for up to eight devices on one I²C bus.

Technical Context

The 24LC128-E/SM implements a two-wire I²C interface with slave addressing using A0–A2 pins, supporting up to eight devices on a shared bus. Its internal architecture includes a 64-byte page latch, address pointer, and EEPROM array with self-timed erase/write cycles.

It uses Schmitt-trigger inputs on SDA and SCL for robust noise suppression and slope-controlled outputs to minimize ground bounce. Write protection is enforced by the WP pin, sampled at the Stop bit of each write command, and is effective across the full 0000h–3FFFh memory map.

Key Specifications

Parameter	Value and Actual Design Meaning
Memory Size	128 Kbit (16,384 × 8 bits); provides sufficient space for device configuration, calibration tables, and event logs in resource-constrained systems.
VCC Range	2.5V to 5.5V; compatible with standard 3.3V and 5V logic rails, excluding sub-2.5V operation unlike 24AA128.
Max Clock Frequency	400 kHz at VCC ≥ 2.5V; enables faster byte/page writes than 100 kHz mode while maintaining timing margin in noisy environments.
Page Write Buffer	64 bytes; allows efficient bulk writes without host-side buffering, reducing I²C transaction overhead and host CPU load.
Endurance & Retention	1,000,000 erase/write cycles and >200 years data retention at 25°C; suitable for long-life industrial deployments with infrequent but critical updates.
Temperature Range	–40°C to +125°C (Extended grade); qualified for under-hood automotive, industrial control, and high-ambient applications.
Write Protection	Hardware-enabled via WP pin tied to VCC; prevents accidental overwrites during power-up/down or firmware glitches without software intervention.

Pinout & Package

24LC128-E/SM is housed in an 8-lead SOIC package (JEDEC MS-012, body width 3.90 mm, suffix "SM"). The package is RoHS-compliant, surface-mountable, and rated for extended temperature operation.

Pin/Terminal	Circuit Role	Design Meaning
A0	Chip Address Input	Configures LSB of 3-bit slave address; must be hardwired to VSS or VCC to select one of eight possible I²C addresses on shared bus.
A1	Chip Address Input	Configures middle bit of slave address; enables multi-device topology without address conflict when combined with A0/A2.
A2	Chip Address Input	Configures MSB of slave address; allows up to eight 24LC128-E/SM devices on same I²C bus for expanded storage capacity.
VSS	Ground Reference	Primary return path for all internal circuitry and I/O; requires low-impedance connection to system ground plane.
SDA	Serial Data I/O	Open-drain bidirectional line for address/data transfer; requires external pull-up resistor (2–10 kΩ depending on speed).
SCL	Serial Clock Input	Master-generated clock synchronizing all I²C transactions; Schmitt-trigger input ensures noise immunity on rising/falling edges.
WP	Write-Protect Control	Active-high enable: tied to VCC disables all writes (reads unaffected); sampled only at Stop condition of write command.
VCC	Power Supply	Single supply input (2.5–5.5V); powers EEPROM core, interface logic, and charge pump for write operations.

Key Features

Feature	Design Value
Page Write Capability	64-byte buffer enables single I²C transaction to store a full page-reducing bus occupancy and host interrupt load vs. byte-by-byte writes.
Schmitt Trigger Inputs	SDA/SCL inputs feature hysteresis (≥0.05×VCC), rejecting fast transients and enabling reliable operation in electrically noisy industrial environments.
Self-Timed Write Cycle	No external timing control needed; internal controller manages erase/write sequence, freeing host MCU from polling or fixed delays.
Hardware Write Protection	WP pin provides fail-safe, zero-software-dependency lockout-critical for preventing corruption during brown-out or reset conditions.
Cascadable Architecture	Three address pins (A0–A2) allow up to eight 24LC128-E/SM devices on one I²C bus, scaling total addressable space to 1 Mbit without additional controllers.

Applications

Industrial Sensor Calibration	Smart Energy Metering
Use Scenario: Storing factory-calibrated offset/gain coefficients and temperature compensation curves for analog sensor front-ends in programmable logic controllers. IC Role / Device Role / Timing Role: Nonvolatile configuration storage accessed at power-on; retains values across 10+ year field life with no battery backup. Use Value: Eliminates manual recalibration; enables traceable, revision-controlled calibration data with >200-year retention and 1M-cycle endurance.	Use Scenario: Recording tariff schedules, demand-response settings, and tamper-event logs in DIN-rail mounted electricity meters operating at 125°C ambient. IC Role / Device Role / Timing Role: Extended-temperature EEPROM interfacing directly with metrology SoC via I²C; withstands thermal cycling and ESD events per IEC 61000-4-2. Use Value: Ensures regulatory compliance via secure, write-protected parameter storage; WP pin prevents unauthorized firmware or tariff changes.
Automotive Body Control Module	Medical Device Configuration
Use Scenario: Saving user preferences (mirror position, seat memory), fault codes, and adaptive learning parameters in BCMs exposed to under-hood temperatures. IC Role / Device Role / Timing Role: AEC-Q100 qualified EEPROM providing persistent storage for safety-critical configuration data with deterministic read/write latency. Use Value: Meets automotive reliability requirements: –40°C to +125°C operation, >1M endurance, and hardware write-lock for ASIL-B relevant functions.	Use Scenario: Storing FDA-mandated calibration constants, usage counters, and audit trails in portable infusion pumps and diagnostic handhelds. IC Role / Device Role / Timing Role: Secure, low-power nonvolatile memory for medical-grade data integrity; accessed only during boot or maintenance mode. Use Value: Supports ISO 13485 traceability with guaranteed 200-year data retention and write-protection against accidental overwrite during field servicing.

Industrial Sensor Calibration

Smart Energy Metering

Use Scenario: Storing factory-calibrated offset/gain coefficients and temperature compensation curves for analog sensor front-ends in programmable logic controllers.

IC Role / Device Role / Timing Role: Nonvolatile configuration storage accessed at power-on; retains values across 10+ year field life with no battery backup.

Use Value: Eliminates manual recalibration; enables traceable, revision-controlled calibration data with >200-year retention and 1M-cycle endurance.

Use Scenario: Recording tariff schedules, demand-response settings, and tamper-event logs in DIN-rail mounted electricity meters operating at 125°C ambient.

IC Role / Device Role / Timing Role: Extended-temperature EEPROM interfacing directly with metrology SoC via I²C; withstands thermal cycling and ESD events per IEC 61000-4-2.

Use Value: Ensures regulatory compliance via secure, write-protected parameter storage; WP pin prevents unauthorized firmware or tariff changes.

Automotive Body Control Module

Medical Device Configuration

Use Scenario: Saving user preferences (mirror position, seat memory), fault codes, and adaptive learning parameters in BCMs exposed to under-hood temperatures.

IC Role / Device Role / Timing Role: AEC-Q100 qualified EEPROM providing persistent storage for safety-critical configuration data with deterministic read/write latency.

Use Value: Meets automotive reliability requirements: –40°C to +125°C operation, >1M endurance, and hardware write-lock for ASIL-B relevant functions.

Use Scenario: Storing FDA-mandated calibration constants, usage counters, and audit trails in portable infusion pumps and diagnostic handhelds.

IC Role / Device Role / Timing Role: Secure, low-power nonvolatile memory for medical-grade data integrity; accessed only during boot or maintenance mode.

Use Value: Supports ISO 13485 traceability with guaranteed 200-year data retention and write-protection against accidental overwrite during field servicing.

Equivalent & Alternatives

The following parts are listed as comparable options for similar serial EEPROM applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
24AA128-I/SM	Wider VCC range (1.7–5.5V); lower 100 kHz max clock below 2.5V; Industrial temp only (–40°C to +85°C).	Preferred for battery-powered or 1.8V systems; unsuitable for extended-temp or 125°C environments.	Select 24AA128-I/SM only if sub-2.5V operation is required and extended temperature is not needed.
AT24C128N-10SU-2.7	Same 128 Kbit size and SOIC-8 package; 1 MHz I²C support; 1.8–5.5V VCC; 1M endurance; no AEC-Q100 qualification.	Higher-speed option for 3.3V systems needing faster writes; lacks automotive qualification and extended-temp rating.	Choose AT24C128N-10SU-2.7 when 1 MHz I²C throughput is critical and AEC-Q100 is not required.

Compared with 24LC128-E/SM, the 24AA128-I/SM offers broader voltage flexibility but sacrifices extended temperature capability, while the AT24C128N-10SU-2.7 provides higher I²C speed but no automotive qualification-making 24LC128-E/SM the optimal choice for ruggedized, high-reliability extended-temp designs.

Availability

24LC128-E/SM is available at Aetrix Electronics and suitable for industrial sensor calibration, smart energy metering, and automotive body control modules requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for 24LC128-E/SM 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

Microchip Technology Inc. is a leading provider of microcontrollers, analog components, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24LC128 belongs to Microchip's 24XX128 family of I²C serial EEPROMs, engineered for robust, low-power nonvolatile storage in industrial, automotive, and medical applications demanding extended temperature operation and high data integrity.

FAQ

What is the maximum I²C clock frequency supported by the 24LC128-E/SM?

The 24LC128-E/SM supports up to 400 kHz I²C clock frequency when VCC is 2.5V or higher. It does not support the 1 MHz mode available in the 24FC128 variant. This 400 kHz limit ensures reliable timing margins across its full –40°C to +125°C operating range and aligns with standard I²C Fast-mode specifications.

Does the 24LC128-E/SM require external pull-up resistors on SDA and SCL lines?

Yes, the 24LC128-E/SM requires external pull-up resistors on both SDA and SCL lines because these pins are open-drain. Typical values are 2 kΩ for 400 kHz operation and 10 kΩ for 100 kHz. The exact value depends on bus capacitance and desired rise time, as specified in the AC characteristics table of the 24LC128-E/SM datasheet.

How does hardware write-protection work on the 24LC128-E/SM?

Hardware write-protection on the 24LC128-E/SM is controlled by the WP pin: when tied to VCC, all write operations (byte and page) are inhibited while read operations remain fully functional. The WP state is sampled at the Stop condition of each write command, making it effective even during power transitions or brown-out conditions.

Can multiple 24LC128-E/SM devices share the same I²C bus?

Yes, up to eight 24LC128-E/SM devices can share one I²C bus using the A0, A1, and A2 address pins to configure unique 3-bit slave addresses. Each device must have a distinct combination of A0–A2 tied to VSS or VCC; the base I²C address is 1010b, followed by these three bits and the R/W bit.

What is the page write buffer size of the 24LC128-E/SM, and why does it matter?

The 24LC128-E/SM has a 64-byte page write buffer. This means up to 64 bytes can be loaded into the buffer and written to memory in a single I²C transaction after the Stop condition. It reduces bus traffic, minimizes host MCU intervention, and improves system efficiency compared to byte-wise writes-especially in high-throughput logging or configuration update scenarios.

24LC128-E/SM Specifications

Product attributes: Attribute value

Manufacturer:: Microchip Technology

Series:: -

Package/Case:: 8-SOIC (0.209", 5.30mm Width)

Packaging:: Tube

Product Status:: Active

Programmable:: Verified

Memory Type:: Non-Volatile

Memory Format:: EEPROM

Technology:: EEPROM

Memory Size:: 128Kbit

Memory Organization:: 16K x 8

Memory Interface:: I2C

Clock Frequency:: 400 kHz

Write Cycle Time - Word, Page:: 5ms

Access Time:: 900 ns

Voltage - Supply:: 2.5V ~ 5.5V

Operating Temperature:: -40°C ~ 125°C (TA)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: 8-SOIJ

24LC128-E/SM FAQ

1.How can I place an order for 24LC128-E/SM through Aetrix?

Please submit a Request for Quotation (RFQ) for 24LC128-E/SM 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 24LC128-E/SM reliable?

The price and inventory of 24LC128-E/SM are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 24LC128-E/SM is usually 5 days.

3.What payment methods are accepted for 24LC128-E/SM?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 24LC128-E/SM transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for 24LC128-E/SM?

24LC128-E/SM orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your 24LC128-E/SM 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 24LC128-E/SM?

For technical support, including 24LC128-E/SM datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 24LC128-E/SM requirements.

6.How does Aetrix verify that 24LC128-E/SM is sourced from the original manufacturer or authorized distributors?

All 24LC128-E/SM 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 24LC128-E/SM meets industry standards.

7.What is the process for return or replacement of 24LC128-E/SM?

All 24LC128-E/SM units undergo pre-shipment inspection (PSI). If there is an issue with 24LC128-E/SM, 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 24LC128-E/SM part is unused and in its original packaging.

Return procedure for 24LC128-E/SM:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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