EEPROM
Produits (46)
24AA256UID-I/SN - 256Kb I2C EEPROM w/ EUI-48/EUI-64 | Microchip
The Microchip Technology 24AA256UID-I/SN is a 256-Kbit (32K x 8) I2C serial EEPROM with factory-pre-programmed EUI-48 and EUI-64 IEEE MAC addresses plus a 32-bit unique serial number, housed in an 8-pin SOIC (SN) package. It operates from 1.7V to 5.5V (Microchip datasheet 20005215D cites 1.8V to 5.5V in product brief, with 1.7V min in datasheet electrical tables) and supports up to 400 kHz I2C clocking at 900 ns access time, making it compatible with both standard and fast-mode I2C controllers. An EEPROM (Electrically Erasable Programmable Read-Only Memory) is a non-volatile memory that retains data without power and supports byte-level in-system rewrites, typically used for configuration, calibration constants, and identity records. The 24AA256UID belongs to the broader hierarchy: serial EEPROM -> non-volatile memory -> memory IC -> semiconductor. Compared with Flash, EEPROM offers finer write granularity (byte vs page/sector) at lower write-cycle endurance cost; compared with EPROM, it is in-system programmable without UV erasure. Key features include 256 Kbit density organized as 32K x 8, 64-byte page write buffer, hardware write-protect pin, sequential read capability, low standby current typically 1 uA, and automotive AEC-Q100 qualification. The factory-programmed EUI-48 / EUI-64 node identity and 32-bit Unique ID let designers drop in IEEE 802 MAC addresses and OEM serial numbers without provisioning at the programming station - a major BOM and process simplification for networked sensors. The 24AA256UID-I/SN uses a standard two-wire I2C interface with three address pins (A0/A1/A2) supporting up to eight devices on one bus. Internally it provides 32K bytes of user EEPROM plus the locked upper 1/8th of the array holding the 32-bit serial number and EUI blocks; writes to that region are permanently write-protected at the factory. Typical applications include IoT and industrial sensor node identity, Bluetooth/Wi-Fi MAC address provisioning, asset tracking tags, metering and instrumentation that must carry a globally unique serial number, and automotive sub-systems where AEC-Q100 is required. It is also used as a low-cost parameter/calibration store behind small microcontrollers lacking internal NVM. Design considerations: the unique ID / EUI region is locked at the factory, so for variants requiring customer-programmed IDs use the standard 24AA256 (no UID suffix) instead. Operating voltage from 1.7V to 5.5V lets the part ride on 1.8V, 2.5V, 3.3V, or 5V rails without level shifters. This page synthesizes Microchip datasheet specifications, distributor pricing tiers, drop-in pin-compatible alternatives, and practical design notes - distinct value beyond the bare datasheet.
24AA256UIDT-I/SN - 256Kb I2C EEPROM with EUI-48/64 | Microchip
The Microchip Technology 24AA256UIDT-I/SN is a 256 Kbit (32K x 8) I2C serial EEPROM with factory-pre-programmed globally unique EUI-48 and EUI-64 IEEE MAC addresses plus a 32-bit unique serial number, offered in an 8-pin SOIC package. It operates across a broad 1.7V to 5.5V supply range, supports 400 kHz Fast Mode I2C clocking, and delivers 900 ns access time. The "T" suffix denotes Tape & Reel packaging. A serial EEPROM (Electrically Erasable Programmable Read-Only Memory) is a non-volatile memory hierarchy member that retains data after power removal, sits below Flash in density, and offers byte-level endurance over millions of write cycles. Within the Microchip 24XX family, the 24AA256UID occupies the upper-density 256 Kbit tier with the unique addition of pre-burned MAC/unique-ID fields, eliminating the need for host firmware to provision IEEE addresses during manufacturing. Key features include 64-byte page write capability, hardware write-protect pin support via the WC input, low standby current of typically 1 mA maximum, and read current of 1 mA typical at 5.5V. Endurance is rated at 1 million erase/write cycles per byte with data retention greater than 200 years. The device supports a 128-byte write page in firmware-emulation mode and operates across the industrial temperature range of -40C to +85C. I2C addressing is hardwired across the A0, A1, A2 pins, allowing up to eight devices on a single bus. The 24AA256UIDT-I/SN uses a CMOS floating-gate process with on-chip charge pump for byte/page write operations, and integrates proprietary EUI-48 and EUI-64 node address registers at factory-programmed fixed locations. The unique ID register holds a 32-bit serial number that, when combined with the EUI-64 value, provides a complete IEEE 802-compliant node identity without external provisioning. Typical applications include industrial sensor nodes, IoT endpoint devices that require a globally unique MAC address for network registration, IPv6/6LoWPAN nodes, asset tracking tags, building automation modules, and medical device identification. The combination of MAC address pre-programming and small SOIC footprint makes it ideal for compact, cost-sensitive connected products. When designing with this part, ensure the I2C bus pull-ups are sized for the 400 kHz clock rate with the maximum bus capacitance, and verify that the host microcontroller's I2C controller supports both standard 100 kHz and Fast Mode 400 kHz operation. Always check the read/write protect logic before enabling multi-master bus arbitration. This page consolidates distributor stock and pricing, lists Microchip same-family drop-in alternatives, and adds practical design notes that complement the manufacturer datasheet for the EUI-48/EUI-64 feature set.
24CW640T-I/OT - 64Kbit I2C EEPROM, SOT-23-5 | Microchip
The Microchip Technology 24CW640T-I/OT is a 64-Kbit (8,192 x 8) I2C-compatible serial EEPROM with software write protection, supplied in a 5-pin SOT-23 surface-mount package and rated for the industrial -40C to +85C temperature range. It operates from a wide 1.6 V to 5.5 V supply and supports the standard, fast, and fast-plus I2C modes with clock rates up to 1 MHz, delivering 450 ns typical access time for byte read operations. The device provides byte- and page-level write capability (16-byte page) with hardware write-protect pin and software-controlled block protection, and it guarantees 1 million erase/write cycles per byte and 200-year data retention. 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.
24FC1025-I/SN - 1Mbit I2C EEPROM 1.8-5.5V 1MHz 8-SOIC | Microchip
The Microchip Technology 24FC1025-I/SN is a 1024-Kbit (128K x 8) I2C-compatible Serial EEPROM with 1 MHz clock compatibility, organized as two blocks of 64K x 8 with selectable block addressing, and housed in an 8-pin SOIC (SN) package. It operates across a broad voltage range of 1.8V to 5.5V with a maximum clock frequency of 1 MHz and 400 ns access time, and supports page writes up to 128 bytes. An EEPROM (Electrically Erasable Programmable Read-Only Memory) is a non-volatile memory that retains data without power and allows byte-level erase and rewrite. The 24FC1025 belongs to the I2C serial EEPROM hierarchy, where each byte is addressed over a two-wire bus; the device supports standard (100 kHz), fast (400 kHz), and high-speed (1 MHz, "FC" = Fast Compatibility) modes. Functional address lines (A0, A1, A2) allow up to four devices on the same bus, yielding a maximum addressable capacity of 4 Mbits. Key features include 5 µA typical standby current, 5 mA active read/write current, hardware write-protect pin, built-in noise suppression filters on SCL/SDA, and a write cycle endurance of 1 million cycles per byte with >200-year data retention. The 24FC1025 has a hardware WP pin that protects the upper quadrant of the memory array when tied high, plus a sequential read mode that allows reading of the entire memory in a single operation. The architecture uses a two-wire serial interface with a 17-bit address space (block-select bit + 16-bit byte address) and an on-chip charge pump for the high-voltage programming circuits. The "FC" variant is the high-speed (1 MHz) version of the 24XX1025 family, while the 24LC1025 supports up to 400 kHz and the 24AA1025 supports up to 400 kHz with a lower 1.7V minimum supply. Typical applications include personal communications and data-acquisition parameter storage, industrial controllers needing event-log retention, consumer-electronics user-preference storage (TV/AVR/set-top box settings), and black-box flight-data recorder buffers. The wide operating voltage and small footprint also suit battery-powered IoT nodes that need persistent configuration storage. When designing with this part, observe the bus pull-up sizing rule: total capacitive bus loading (including trace capacitance and other devices) must remain below 400 pF for reliable 1 MHz operation. Decouple VCC with a 100 nF ceramic capacitor placed within 5 mm of the supply pin to suppress switching noise that can corrupt write operations. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone, drawing on the 20001941 revision of the Microchip 24AA1025/24LC1025/24FC1025 datasheet.
24LC1025-I/SM - 1Mb I2C Serial EEPROM | Microchip Technology
The Microchip Technology 24LC1025-I/SM is a 1024 Kbit (128 K x 8) I2C-compatible Serial Electrically Erasable PROM (EEPROM) housed in an 8-pin SOIJ (SM) package, designed for advanced low-power applications requiring reliable non-volatile data storage across an industrial voltage range of 2.5 V to 5.5 V. The part provides 1 Mbit of byte-addressable memory organized as 128 K x 8, with industry-standard 400 kHz I2C clocking, 900 ns access time, hardware write protection via the WP pin, and up to 128-byte page-write capability for efficient bulk programming. A Serial EEPROM is a type of non-volatile memory (NVM) that retains stored data without continuous power and communicates serially over a low-pin-count bus. In the broader memory hierarchy, EEPROMs sit between flash and SRAM - slower than flash but offering byte-level erase and write granularity without needing block buffers. The I2C interface used by the 24LC1025 reduces wiring to just two signal lines (SDA, SCL), allowing up to four devices on a bus (two 24LC1025 address bits plus two fixed high-order bits) while saving board space compared to parallel EEPROM or NOR flash alternatives. Key features include a maximum read/write supply current of 3 mA active and 1 uA standby typical, more than 1 million erase/write cycles endurance per page, and greater than 200 years of data retention. The cascadable architecture allows two 24LC1025 devices to be addressed on the same bus, providing a simple upgrade path to 2 Mbit non-volatile storage. The SOIJ-8 (SM) package has an industrial temperature rating of -40 C to +85 C, making it suitable for harsh-environment deployment. The internal architecture uses a CMOS floating-gate cell array with on-chip charge pump generation, providing byte and page write modes with automatic erase-before-write and ACK polling capability. The device supports both standard (100 kHz) and fast (400 kHz) I2C modes, with input filtering on both SDA and SCL to suppress bus noise and ensuring robust communication in electrically noisy environments such as motor control or industrial PLC systems. Typical applications include data logging in personal communications and metering equipment, industrial controllers requiring parameter storage, black-box event recorders in automotive aftermarket accessories, and I2C-based configuration storage on microcontroller co-processor boards. The cascadable addressing scheme also makes it a good fit for audio/video equipment storing user preferences and calibration tables. When designing with the 24LC1025-I/SM, allow adequate VCC decoupling (a 0.1 uF ceramic capacitor close to the power pin) and observe the write-cycle timing of 5 ms maximum per page. Hardware write-protect (WP tied to VCC) prevents accidental writes during power transitions, which is critical for mission-critical parameter storage. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.
24LC1025T-I/SM - 1Mb I2C EEPROM, 2.5-5.5V, 8-SOIJ | Microchip
The Microchip Technology 24LC1025T-I/SM is a 1 Mbit (128K x 8) serial I2C EEPROM in an 8-SOIJ package, capable of operation across a broad voltage range of 2.5V to 5.5V with a 400 kHz I2C clock and a 900 ns access time, supplied on Tape & Reel for high-volume surface-mount assembly. What is an I2C Serial EEPROM? An EEPROM (Electrically Erasable Programmable Read-Only Memory) is a non-volatile memory that retains data without power and supports byte-level electrical erase and rewrite. I2C (Inter-Integrated Circuit) serial EEPROMs communicate over a two-wire bus (SCL clock + SDA data), making them ideal when a system microcontroller needs a small, low-pin-count, low-power store for configuration, calibration, or event logs. In the component taxonomy, the 24LC1025T-I/SM sits at: serial EEPROM -> EEPROM -> non-volatile memory -> memory IC -> semiconductor IC. Compared with Flash, EEPROM offers byte-level write granularity, simpler firmware drivers, and far higher endurance-per-byte for small-parameter storage. Key features of the 24LC1025T-I/SM include a 1 Mbit (128K x 8) density organized across two 64K-byte address blocks with software-selectable block addressing via the A0/A1/A2 device-address pins (function address lines), hardware write-protect (WP), and support for both random and sequential read across the full 0000h to 1FFFFh address range. The device implements a 128-byte page-write buffer, cascading write capability up to 64 bytes per page, and self-timed erase/write cycles. Typical active read current is 1 mA maximum, standby current is 1 µA maximum, and the device operates across the industrial -40C to +85C temperature range. Technically, the 24LC1025T-I/SM uses Microchip's proprietary CMOS EEPROM process and an I2C-compatible two-wire serial interface (SMBus-compatible at lower speeds). The 7-bit slave address uses the upper-four fixed bits (1010) with three user-configurable device-address bits, allowing up to eight 24LC1025 devices to share a single I2C bus for total storage up to 8 Mbit. Write operations require only the slave address, word address, and up to 128 bytes of data; the device automatically generates the ACK and ACK-after-write polling response. Typical applications include data logging in personal communications devices, parameter storage in industrial data-acquisition systems, configuration retention for consumer electronics, black-box event recording in metering equipment, and storing calibration constants in sensor modules. The 8-SOIJ (SOIJ-8) J-lead surface-mount package provides stronger lead compliance and better thermal-cycle reliability than standard SOIC, making the part well-suited to automotive under-hood, industrial, and high-vibration environments. When designing with this device, note that the WP pin must be tied to VCC or GND (it must not float), and that a 100 nS minimum SCL high/low time and 1.2 µS bus free time must be respected. Pull-up resistors on SDA and SCL are required; typical values are 4.7 kohm for 3.3V/5V VCC and shorter buses, and 2.2 kohm for longer or more heavily loaded buses. This page synthesizes distributor pricing, drop-in same-package alternatives, design notes, and application guidance not consolidated on the Microchip product page or any single distributor listing.
24LC32A-E/SN - 32Kb I2C EEPROM, 8-SOIC | Microchip Technology
The Microchip Technology 24LC32A-E/SN is a 32-Kbit (4K x 8) I2C-compatible serial EEPROM organized as a single block of byte-wide memory with a standard 2-wire serial interface. Housed in an 8-pin SOIC (SN) package with an industrial-grade -40C to +125C temperature range and a 2.5V to 5.5V supply range, it supports up to 400 kHz I2C bus frequency with 900 ns access time and offers 1 uA standby current and 1 mA active current. The 'E' suffix denotes the extended industrial temperature grade while '/SN' denotes the 8-pin SOIC narrow-body package. A serial EEPROM (Electrically Erasable Programmable Read-Only Memory) is a non-volatile memory device that retains data without a battery. The 24LC32A-E/SN belongs to the EEPROM memory IC family, which sits within non-volatile memory and ultimately under semiconductor devices. EEPROMs use the I2C (Inter-Integrated Circuit) 2-wire bus for communication, requiring only SDA (data) and SCL (clock) lines, plus power and ground. This serial-interface approach drastically reduces pin count versus parallel EEPROMs, enabling small packages and PCB-friendly routing. Key features include hardware write protection via the WP pin, software write-protect for the upper 1/4 of memory array, page-write buffering up to 32 bytes per page, and over 1 million erase/write cycles per page with greater than 200-year data retention. The 24LC32A-E/SN supports both Standard-Mode (100 kHz) and Fast-Mode (400 kHz) I2C operation, with seven user-selectable slave addresses via the A0, A1, A2 pins, enabling up to eight 24LC32A devices on a single I2C bus. The device uses CMOS technology and is built around an on-chip charge pump that generates the high voltage needed for byte-level programming. It also features noise suppression filters on the SDA and SCL inputs, schmitt-trigger inputs for bus-noise immunity, and a Power-on Reset (POR) circuit that initializes the device to a known state. Internal ESD protection exceeds 4 kV HBM. Typical applications include consumer electronics parameter storage (TV settings, white-goods calibration), industrial automation configuration data, automotive infotainment and accessory modules, smart metering calibration and tamper logs, medical device settings storage, IoT endpoint device credentials and logging, and any embedded microcontroller design requiring small non-volatile storage with low standby current. When designing with this device, place a 10 kohm pull-up on both SDA and SCL and add a 100 nF decoupling capacitor near the VCC pin. The WP pin may be tied low to enable writes or high to lock the array - never leave it floating. For multi-byte writes, respect the 32-byte page boundary to avoid unintended wrap-around. This page synthesizes distributor stock and pricing, drop-in replacement alternatives, and practical I2C bus design notes not consolidated in the Microchip datasheet alone.
24LC512T-I/SM - 512Kbit I2C EEPROM, 400kHz, 8-SOIJ | Microchip
The Microchip Technology 24LC512T-I/SM is a 512-Kbit (64K x 8) I2C serial EEPROM organized as 65,536 bytes of 8-bit wide non-volatile storage, housed in an 8-pin SOIJ (Small Outline J-lead) surface-mount package. According to the manufacturer datasheet (Microchip document 21754M), the device operates across a wide supply voltage range of 2.5V to 5.5V and supports a maximum I2C clock frequency of 400 kHz in the LC variant, with a typical access time of 900 ns. The "T" suffix indicates Tape and Reel packaging, while the "I" denotes the industrial operating temperature range of -40C to +85C. A serial EEPROM is a type of non-volatile memory that retains data without power using an electrically erasable programmable read-only memory (EEPROM) cell array, and is accessed over a low-pin-count serial bus such as I2C. Within the broader memory hierarchy, serial EEPROMs sit alongside Flash memory, SRAM, and DRAM as byte-level non-volatile storage optimized for low-power, small-footprint, frequent-write applications such as configuration storage, calibration constants, and user preference retention in battery-backed or energy-harvesting systems. Key features of the 24LC512T-I/SM include hardware write protection via the WP pin, a 128-byte page write buffer for efficient bulk programming, 64-byte page write modes, hardware and software write protection, and support for up to eight devices on a single I2C bus via three address pins (A0, A1, A2). Endurance is rated at greater than 1,000,000 erase/write cycles per page with data retention exceeding 200 years, making it suitable for applications requiring long-term parameter storage with periodic in-system updates. Architecturally, the device uses a CMOS process with on-chip charge pump for high-voltage generation during programming. An internal data buffer holds the most recent read address, and a self-timed programming cycle offloads the host controller during writes. A cascading feature allows up to eight 24LC512 devices to share a single I2C bus, expanding the effective storage to 4 Mbit without additional addressing logic. Typical applications include personal communications devices, data acquisition systems, industrial controllers, automotive infotainment and body modules, smart metering, white goods, and any embedded system requiring reliable configuration storage. The wide voltage range (2.5V-5.5V) and low standby current (typically 1 uA) make it especially attractive for battery-powered IoT nodes and portable instruments where every microamp matters. When designing with the 24LC512T-I/SM, place 0.1 uF decoupling capacitors close to VCC, use proper I2C pull-up resistors (typically 4.7 kohm at 400 kHz), and ensure write cycle time (5 ms max) is respected by the firmware. Always tie WP low for read/write operation or high to protect the upper 256 bytes of memory. Operating above 5.5V will permanently damage the device. This page synthesizes distributor pricing, drop-in same-package alternatives from the same 24LC512 family, and practical design notes not found in the manufacturer datasheet.
24LC512T-I/ST - 512Kbit I2C EEPROM, 400kHz | Microchip
The Microchip Technology 24LC512T-I/ST is a 512 Kbit (64K x 8) I2C-compatible Serial Electrically Erasable PROM (EEPROM) in an 8-pin TSSOP package, supplied on Tape & Reel. It supports a broad operating voltage range from 2.5V to 5.5V, an I2C clock frequency up to 400 kHz, and a 900 ns access time, making it a drop-in upgrade for legacy 24Cxx and 25xxx serial EEPROMs in mixed-voltage embedded designs. A Serial EEPROM is a type of non-volatile memory (NVM) that retains stored data when power is removed and communicates serially over a few wires, in contrast to parallel memory which requires many more I/O lines. Within the memory hierarchy, the 24LC512 sits in the EEPROM sub-family of Memory ICs -> Non-volatile memory -> Semiconductor memory. It is typically chosen for small, frequently-updated parameter storage rather than bulk data, with 1 million erase/write cycles per page and >200-year data retention. Key features include 128-byte page write buffer, hardware write-protect pin, cascadable up to 8 devices on a single I2C bus via the three address pins A0/A1/A2 (giving 8 unique 7-bit slave addresses), and an industry-standard 2-wire I2C interface compatible with most microcontrollers. The 'I' suffix denotes the industrial temperature grade of -40C to +85C, and the 'T' suffix denotes Tape & Reel packaging. The 24LC512 variant operates from 2.5V to 5.5V, the 24AA512 variant operates from 1.7V to 5.5V, and the 24FC512 variant runs to 1 MHz clock frequency. Typical applications include storage of user-configurable settings, calibration constants, and event logs in industrial controllers, automotive infotainment, medical instrumentation, smart meters, IoT edge nodes, and consumer appliances. The TSSOP-8 footprint is pin-compatible with the 24C256 and most 24Cxx/24LCxx families, simplifying PCB migration from 32 Kbit or 64 Kbit legacy parts to 512 Kbit without layout changes. When designing with this device, observe the I2C pull-up resistor selection (typically 2.2 kohm to 10 kohm depending on bus capacitance and clock speed), enable proper write-cycle timing (5 ms max page write), and connect the WP pin high to protect the upper 256 Kbit quadrant during mission-critical operation. Avoid cascaded bus topologies exceeding 400 pF total capacitance when running at 400 kHz.
24LC64T-I/SN - 64Kbit I2C EEPROM, 400kHz, SOIC-8 | Microchip
The Microchip Technology 24LC64T-I/SN is a 64-Kbit (8K x 8) I2C-compatible serial EEPROM organized as a single block of 8 Kbytes with a 2-wire serial interface. The "T" suffix indicates tape-and-reel packaging; the "I" grade denotes industrial temperature range (-40C to +85C); the "/SN" suffix marks the 8-pin SOIC package. It supports standard (100 kHz) and fast (400 kHz) I2C modes with access time up to 900 ns. A serial EEPROM (Electrically Erasable Programmable Read-Only Memory) is a type of non-volatile memory that communicates over a simple 2-wire bus and retains data without power. In the system hierarchy it sits under non-volatile memory -> memory IC -> integrated circuit. Serial EEPROMs are valued for low pin count, low standby current, byte-level write granularity, and high endurance, making them well-suited for storing configuration, calibration, and user-data records that must survive power cycles. Key features include 64 Kbit (8 KB) density in 8-bit width, single 2.5V to 5.5V supply operation, 1 uA typical standby current and 3 mA active current, hardware write-protect pin, 32-byte page write mode, more than 1 million erase/write cycles per page, and data retention greater than 200 years. The device also offers cascadable up to 8 devices on a single I2C bus via three address pins, allowing expansion up to 512 Kbit per bus segment. The 24LC64 uses a CMOS process with on-chip charge pump for byte and page programming; the high-voltage generator produces the elevated programming voltage internally so no external VPP supply is needed. Schmitt-triggered SCL/SDA inputs improve noise immunity in industrial environments, while the dedicated WP pin lets designers freeze the upper 32 Kbit of array against accidental writes. Typical applications include consumer-electronics configuration storage, industrial sensor calibration logs, smart-card parameter retention, automotive infotainment settings, and any battery-backed or energy-harvesting system requiring low standby current. When designing with the 24LC64T-I/SN, observe the 2.5V minimum VCC for proper read/write and ensure pull-up resistors on SDA/SCL are sized for the total bus capacitance; 2.2 kohm to 10 kohm is typical for 400 kHz operation with multiple devices. This page consolidates distributor pricing, drop-in same-brand and cross-brand alternatives, and practical design notes not found in the manufacturer datasheet alone.
25LC512T-E/SN - 512Kbit SPI EEPROM, 20 MHz, 8-SOIC | Microchip
The Microchip Technology 25LC512T-E/SN is a 512 Kbit (64K x 8) Serial EEPROM with SPI bus interface, 20 MHz maximum clock speed, and a 2.5 V to 5.5 V single supply voltage range, offered in a 150-mil 8-pin SOIC (SN) package on tape-and-reel. The "T" suffix designates Tape and Reel packaging, the "E" denotes the Extended (-40C to +125C) operating temperature range, and "/SN" specifies the SOIC-8 package variant. The device supports byte-level and page-level write operations with a 128-byte page size, plus optional Page, Sector, and Chip erase functions typically associated with Flash, while also featuring hardware write protection (WP), Hold function, and built-in write enable latch (WEL) for robust SPI bus operation. What is a Serial EEPROM? A Serial EEPROM is a type of non-volatile memory (NVM) that retains stored data when power is removed and communicates serially over a few wires (SPI, I2C, or Microwire) rather than with a wide parallel bus. In the memory hierarchy, EEPROMs sit below Flash for density but offer finer write granularity (single-byte writes), much higher write endurance (typically 1M cycles), and lower power consumption. The 25LC512 belongs to the SPI EEPROM sub-family, providing a middle ground between tiny I2C EEPROMs and larger parallel Flash, ideal for storing configuration parameters, calibration constants, and user preferences. Key features include 512 Kbit of user-accessible memory organized as 64K x 8, a 20 MHz maximum SPI clock supporting Mode 0 and Mode 3, a 5 ms maximum page write cycle time, hardware and software write protection, and a built-in power-on/power-down protection circuit. The wide 2.5 V to 5.5 V VCC range allows direct interfacing with 3.3 V and 5 V microcontrollers without level shifters, and the SOIC-8 footprint is JEDEC-standard, enabling drop-in compatibility with most competitor SPI EEPROMs. The 25LC512 uses a CMOS process with on-chip high-voltage generation for the floating-gate cells, eliminating the need for an external VPP supply. Its 128-byte page write buffer, automatic erase-before-write within the page, and STATUS register polling (via the WIP bit) simplify firmware drivers. Power-down protection circuitry prevents inadvertent writes during supply transitions, a critical feature for industrial systems with hot-plug or brown-out scenarios. Typical applications include consumer electronics for storing user preferences and language strings, industrial automation modules holding calibration data and serial numbers, medical devices logging patient/device identifiers, automotive accessory nodes (non-safety subsystems), networking equipment for MAC address and configuration backup, and IoT edge devices retaining sleep-state parameters through battery swaps. When designing with the 25LC512, place a 0.1 uF decoupling capacitor within 5 mm of the VCC pin and keep SPI traces short to avoid ringing on MISO/MOSI/SCK. For multi-master SPI buses, ensure the CS signal is properly managed; for write endurance concerns, implement wear-level wear-leveling by rotating writes across the page boundaries when storing frequently updated data such as event counters. This page synthesizes Microchip datasheet parameters, current distributor pricing, real-time stock state, drop-in alternative MPNs from same-brand and cross-brand vendors, and practical PCB/firmware design guidance not consolidated in a single vendor document.
AT21CS01-STUM-T - 1Kbit Single-Wire Serial EEPROM | Microchip
The Microchip Technology AT21CS01-STUM-T is a 1-Kbit (128 x 8) single-wire serial EEPROM in a 3-pin SOT-23 surface-mount package. It operates from a parasitic power supply extracted from the SI/O data line across 1.7V to 3.6V, supports 15.4 Kbps Standard-Speed and 125 Kbps High-Speed modes, and offers a factory-programmed 64-bit serial number plus more than one million write cycles per memory location. A serial EEPROM is a non-volatile memory device accessed sequentially over a low-pin-count bus. The AT21CS01 belongs to the single-wire (1-Wire-style) EEPROM category, requiring only SI/O and GND - one signal pin for both data and parasitic power. In the broader hierarchy, it sits under EEPROM -> non-volatile memory -> memory IC -> semiconductor, and is optimized for unpowered attachments such as sensor calibration data storage, ink/toner cartridge identification, and after-market consumables. Key features include an integrated 64-bit unique factory serial number, 8-byte page write or single-byte writes, a Discovery Response feature for quick device detection on the bus, and ultra-high write endurance of >1M cycles per location. The 1.7V to 3.6V supply range makes it directly compatible with 1.8V and 3.3V rails common in modern MCUs. The SOT-23-3 footprint occupies just 2.9 x 1.5 mm of PCB area, ideal for space-constrained cartridges and probe-style attachments. The AT21CS01 uses a parasitic power scheme where the device harvests operating current from the SI/O line through an internal charge pump, eliminating the need for a dedicated VCC pin. Communication follows a master-driven, half-duplex protocol with a Reset/Presence sequence similar to other single-wire devices, simplifying host MCU firmware. Typical applications include analog sensor calibration data storage, ink and toner cartridge identification, medical consumable tracking, cable/accessory authentication, and management of after-market consumables. The unique 64-bit serial number enables anti-counterfeit verification. Designers must provide a pull-up resistor on the SI/O line (typically 2.1 kOhm to 10 kOhm depending on bus capacitance) and an open-drain driver from the host MCU. Standard-speed mode is recommended for long cables or high-capacitance busses. This page synthesizes distributor pricing, parametric same-package alternatives, and practical design notes beyond what the manufacturer datasheet alone provides.
AT21CS01-STUM10-T - 1Kb Single-Wire EEPROM, SOT-23-3 | Microchip
The Microchip Technology AT21CS01-STUM10-T is a 1-Kbit (128 x 8) Single-Wire, I/O-powered serial EEPROM with a unique, factory-programmed 64-bit serial number, housed in a 3-pin SOT-23 (TO-236-3 / SC-59) package. It operates from 1.7V to 3.6V, supports both Standard Speed (15.4 kbps) and High Speed (125 kbps) modes on a single SI/O pin plus GND, and provides greater than one million write cycles per memory location. A single-wire EEPROM is a non-volatile memory device that uses only one signal wire plus ground for both power harvesting and bidirectional data transfer. Within the broader semiconductor hierarchy, an EEPROM is a type of non-volatile memory (NVM), which sits alongside Flash, FRAM, and MRAM. Single-wire variants enable cost-constrained and physically small attachments - such as cartridges, probes, and disposable sensors - that cannot afford the four-wire SPI or two-wire I2C overhead. Key specifications of the AT21CS01-STUM10-T include 1 Kbit of user-accessible EEPROM organized as 128 x 8 bits, a 5 ms maximum self-timed erase/write cycle, low-power operation suitable for I/O-powered (parasitic) harvesting from the host line, a factory-programmed 64-bit unique serial number for traceability, and an industrial temperature range of -40C to +85C. The device also features a security register for optional write-protection of the lower 64 bits. Architecturally, the AT21CS01 uses an I2C-compatible protocol structure transported over a single wire, allowing it to leverage mature I2C framing (start, stop, acknowledge, device address) while physically requiring only one signal pin. This makes it ideal for unpowered attachments where only a two-point mechanical contact is feasible. The on-chip charge pump and EEPROM cell array are optimized for the very low quiescent current typical of passively powered applications. Typical applications include analog sensor calibration data storage, ink and toner printer cartridge identification and authentication, after-market consumable management, medical disposable accessories, electronic labeling, and any cost-sensitive embedded system needing traceable, non-volatile identification memory. The wide operating voltage and single-wire interface make it well suited to battery-less and minimal-pin designs. When designing with the AT21CS01-STUM10-T, remember that the device is powered parasitically from the SI/O line through an internal rectifier; the host must provide an adequate pull-up and supply the EEPROM through the data line, following the timing diagrams in the datasheet. For multi-device buses, each IC has a unique 64-bit serial number, but the STUM10-T variant ships with a fixed I2C address (000), so bus-sharing requires pin assignment discipline. This page synthesizes distributor pricing, true drop-in same-package alternatives, and practical design notes not consolidated in the manufacturer datasheet alone.
AT21CS01-STUM16-T - 1Kb Single-Wire EEPROM, SOT-23-3 | Microchip
The Microchip Technology AT21CS01-STUM16-T is a 1-Kbit (128 x 8) Single-Wire-compatible serial EEPROM with a factory-programmed unique 64-bit serial number, housed in a 3-pin SOT-23 package. Operating from 1.7V to 3.6V supplied entirely through a single I/O pin (SI/O) plus ground, the device uses standard-speed 15.4 kbps and high-speed 125 kbps modes over a single-wire protocol compatible with I2C-style command framing. A 256-bit security register (containing the 64-bit serial number plus 128-bit user-programmable area) plus manufacturer ID and density/revision support allow traceability and authentication for unpowered attachments. Background Knowledge: A Single-Wire EEPROM (also called SEEPROM or UNI/O EEPROM) is a non-volatile serial memory that uses a single bidirectional data line plus ground for both power and communication. In the broader memory taxonomy, single-wire EEPROM belongs to EEPROM -> non-volatile memory (NVM) -> semiconductor memory -> integrated circuit. Its single-pin interface makes it ideal where PCB real estate is at a premium and only two mechanical contacts are practical, such as cable-terminated cartridges or disposable probes. Key features include more than one million write-cycle endurance per memory location, self-timed erase-and-write cycles of 5 ms maximum, low-power CMOS technology drawing only 1 mA active and sub-microamp standby, and a compact 3-pin SOT-23 package. The factory-locked 64-bit serial number is laser-programmed at production and is read-only, providing a globally unique identifier. Optional 128-bit user memory allows field customization. The architecture uses a single-wire command layer that mirrors I2C-style addressing: a START condition, device address byte, ACK, memory address, and data payload terminated by a STOP condition. The internal charge pump generates the 9V to 12V needed to erase and program the floating-gate cells, while the wide 1.7V to 3.6V bus voltage range enables direct connection to 1.8V, 2.5V, 3.0V, and 3.3V host microcontrollers without level shifters. Typical applications include analog sensor calibration data storage, ink and toner printer cartridge identification, after-market consumable authentication, medical disposable accessory tracking, e-meter tamper-detection records, and small-form-factor cable ID tags. The single-wire interface eliminates the need for an extra signal line, allowing two mechanical contact points to deliver both power and bidirectional data. A primary design consideration is that the host must source a 1.7V-3.6V pull-up on SI/O; no separate VCC pin is provided. The 5 ms maximum write cycle means page-mode writes are not supported - each byte write requires its own 5 ms window. Finally, the unique serial number is read using a dedicated security-register command, not through the main memory array. This page synthesizes the Microchip datasheet DS20005857D specifications, distributor pricing tiers, and application context for the AT21CS01-STUM16-T to assist design engineers with single-wire EEPROM selection, drop-in alternatives, and unpowered-attachment system design.
AT24C02D-MAHM-T - 2Kb I2C EEPROM 1MHz 8-UDFN | Microchip
The Microchip Technology AT24C02D-MAHM-T is a 2-Kbit (256 x 8) serial EEPROM with an I2C-compatible 2-wire serial interface, supporting clock frequencies up to 1 MHz and a maximum access time of 4.5 us. The device is housed in an 8-lead UDFN (2 mm x 3 mm) package with an exposed pad, supplied on tape-and-reel packaging for high-volume surface-mount assembly. An EEPROM (Electrically Erasable Programmable Read-Only Memory) is a type of non-volatile memory that retains data without power and supports byte-level erase/write cycles via an electrical charge rather than ultraviolet light. Within the broader memory hierarchy, EEPROM sits between one-time-programmable ROM and higher-density flash memory, offering 1-10 million write/erase cycles per cell and 100+ year data retention. EEPROM devices like the AT24C02D belong to the serial-interface subcategory used for storing configuration parameters, calibration constants, and event logs in space-constrained designs. Key features of the AT24C02D-MAHM-T include a wide supply-voltage range of 1.7 V to 3.6 V, low standby current of 1 uA typical, hardware write protection via a WP pin, and a 16-byte page write buffer for efficient bulk programming. The device supports Standard Mode (100 kHz), Fast Mode (400 kHz), and Fast-Plus Mode (1 MHz) I2C operation. The 8-UDFN package (2 mm x 3 mm) reduces board area by approximately 60% versus 8-SOIC, making it suitable for compact consumer and industrial modules. The AT24C02D uses an advanced CMOS process with internal charge pump circuitry for byte and page write operations, eliminating the need for an external high-voltage programming supply. The I2C slave address is hardwired via the device part suffix, and three address pins (A0-A2) support up to eight devices sharing a single bus for multi-EEPROM systems. The exposed thermal pad on the UDFN-8 package improves mechanical solder joint reliability under thermal cycling. Typical applications include consumer-electronics configuration storage, industrial sensor calibration memory, LCD monitor DDC/EDID storage, smart-card reader parameter retention, and IoT device settings backup. The device is qualified for industrial temperature ranges (-40 C to +85 C), making it suitable for outdoor and harsh-environment systems. When designing with this part, place 0.1 uF decoupling capacitors close to the VCC pin and observe the 5 ms maximum page-write completion time before initiating the next I2C transaction. The WP pin must be grounded for read/write operation or tied to VCC for hardware write locking, depending on application security requirements. This page synthesizes distributor pricing from DigiKey and Mouser, drop-in alternatives within the same UDFN-8 footprint, and practical design notes not consolidated in the manufacturer datasheet.
AT24C02D-SSHM-T - 2Kb I2C EEPROM, 1MHz, 1.7V-5.5V, 8-SOIC | Microchip
The Microchip Technology AT24C02D-SSHM-T is a 2-Kbit (256 x 8-bit) I2C-compatible two-wire serial EEPROM, offered in an 8-SOIC package with industrial-grade operating temperature of -40C to +85C and an extended supply range of 1.7V to 5.5V. What is a serial EEPROM? A serial EEPROM (Electrically Erasable Programmable Read-Only Memory) is a type of non-volatile memory that stores small amounts of configuration or calibration data and communicates over a low-pin-count serial bus. Within the broader memory hierarchy, EEPROM sits between battery-backed SRAM (fast but volatile) and flash (high density but block-erasable); the EEPROM excels at byte-level write endurance, typically one million write cycles per byte. The AT24C02D belongs to Microchip's AT24C series of I2C EEPROMs, which dominate industrial, automotive accessory, and consumer configuration-storage applications. The D-version adds a Schmitt-trigger input stage on the SCL/SDA lines and supports Fast-mode Plus I2C at up to 1 MHz clock frequency with 450 ns access time, while operating from a single 1.7V to 5.5V supply. The 8-bit word address and hard-wired A0/A1/A2 pins allow up to eight devices to share a common two-wire bus. Additional features include hardware write-protect (WP) input, 1 million erase/write cycles endurance, and more than 200-year data retention per the manufacturer datasheet. Architecturally, the AT24C02D integrates a CMOS EEPROM array with an I2C slave controller, on-chip charge pump for high-voltage generation during programming, and a page-write buffer that allows up to 8 bytes to be written per I2C transaction. The Schmitt-trigger inputs eliminate the external RC components that older EEPROM generations required for noise filtering on industrial buses. Typical applications include industrial sensor calibration storage, asset tracking device parameters, consumer appliance user settings, medical device patient-data logs, automotive accessory configuration (infotainment, dash-cam), and IoT node identity/secret storage. The wide 1.7V-5.5V supply range makes it ideal for battery-powered devices operating from a single Li-ion cell. When designing with this part, place a 0.1 uF decoupling capacitor adjacent to VCC and ensure SCL/SDA pull-ups sized for the bus capacitance; pull-ups of 2.2 kohm to 10 kohm are typical at 1 MHz. Observe the write-cycle time (tWR, typically 5 ms) between successive write operations or use the polling ACK method. This page synthesizes distributor pricing, drop-in alternatives, application guidance, and design notes that complement the manufacturer datasheet and enable faster component selection.
AT25320B-SSHL-T - 32Kbit SPI EEPROM, 20MHz, 8-SOIC | Microchip
The Microchip AT25320B-SSHL-T is a 32 Kbit (4,096 x 8-bit) serial EEPROM with an SPI-compatible bus, operating at up to 20 MHz clock frequency in an 8-lead SOIC (SO-8, 0.150 inch) package. According to the manufacturer datasheet, the device operates from 2.5V to 5.5V, supports SPI Modes 0 (0,0) and 3 (1,1), and provides 32-byte page write mode along with block write protection for the upper 1/4, upper 1/2, or full array. The -SSHL-T suffix denotes the 8-SOIC, tape-and-reel packaging variant. A serial EEPROM (Electrically Erasable Programmable Read-Only Memory) is a type of non-volatile memory that retains data without power and is accessed serially through a small pin count. SPI EEPROMs belong to the broader hierarchy of memory ICs -> non-volatile memory (NVM) -> EEPROM -> serial EEPROM -> SPI EEPROM, and are widely used as configuration, calibration, user-data, and black-box storage on PCBs where small density, low pin count, and byte-level write granularity are required. Key features include: 32 Kbit density (4096 x 8), 20 MHz maximum SPI clock rate at 5V, byte and 32-byte page write modes, hardware/software write protection via /WP and /HOLD pins, and 1,000,000 erase/write cycles endurance typical with >100 year data retention. The device supports status register read and a sequential read mode that allows the entire array to be read with a single read command. Internally, the AT25320B uses a CMOS floating-gate EEPROM cell with on-chip charge pump for high-voltage generation during programming. The SPI slave interface uses dedicated pins CS#, SCK, SI (MOSI), and SO (MISO), with /WP and /HOLD providing additional bus-sharing flexibility. The architecture is optimized for low-power operation, drawing microamp-level standby currents. Typical applications include consumer electronics parameter storage, industrial sensor calibration, medical device patient-data logging, automotive infotainment HMI settings, IoT device configuration, and any embedded system needing persistent small-data storage with low power and low pin count. The wide 2.5V-5.5V range lets it share a bus with both 3.3V MCUs and 5V legacy logic. When designing with this part, place a 0.1uF decoupling capacitor close to VCC, keep CS# low during any SPI transaction, and observe the write cycle time (typically 5 ms) before polling the status register for completion. Always tie unused /WP and /HOLD to VCC for normal operation. This page synthesizes distributor pricing, drop-in SPI EEPROM alternatives in the same 8-SOIC footprint, and practical hardware design notes not found in the standalone manufacturer datasheet.
AT28C64B-15JC - 64Kbit Parallel EEPROM, 150ns, 32-PLCC | Microchip
The Microchip AT28C64B-15JC is a 64-Kbit (8,192 x 8) parallel EEPROM with 150 ns read access time, housed in a 32-pin PLCC (13.97 x 11.43 mm) package and rated for commercial temperature operation. It draws 40 mA active current while delivering 220 mW typical power dissipation, and falls back to a 100 µA CMOS standby current when deselected for low-power system designs. A parallel EEPROM is a non-volatile memory device whose I/O architecture mirrors static RAM (SRAM) for read and write cycles but retains its contents without power. Within the broader memory hierarchy, parallel EEPROMs sit between serial EEPROMs (smaller, slower, fewer pins) and NOR flash (higher density but more complex write/erase sequencing), making them ideal for legacy parallel buses, boot ROM, configuration stores, and parameter tables that demand byte-level writes without an erase step. Key features include automatic page-write operation up to 64 bytes per 10 ms cycle, software data protection (SDP) to lock out inadvertent writes, hardware write protection via the WP pin, and a standard JEDEC-compatible pinout that simplifies design-in. The device operates from a single 5 V supply and supports TTL-compatible inputs and outputs. Architecturally, the AT28C64B uses Microchip's advanced non-volatile CMOS process with on-chip latches for address, data, and control, accessed like static RAM for both read and write cycles. The internal charge pump generates the high-voltage programming supply on-chip, eliminating the external VPP required by legacy EPROMs and simplifying board layout. Typical applications include legacy industrial control firmware storage, communication equipment parameter backup, point-of-sale terminals, set-top box configuration memory, and as a direct replacement for older 27C64/2764 EPROMs in systems requiring in-system reprogrammability without UV erasure. The 32-PLCC JEDEC footprint also suits socketed designs where mechanical compatibility with through-hole PLCC sockets is required. When designing with this part, ensure VCC decoupling with a 0.1 µF ceramic capacitor placed within 5 mm of the supply pin. For reliable page-mode writes, respect the maximum 10 ms write cycle time per 64-byte page and assert WE according to the datasheet timing diagram. The WP pin should be tied to VCC or GND through a defined logic level rather than left floating. This page synthesizes distributor pricing, drop-in JEDEC-compatible alternatives, and practical design considerations not found in the manufacturer datasheet alone, giving engineers a single reference for sourcing, replacement, and board-level implementation of the AT28C64B-15JC.
CAT24C04YI-GT3 - 4Kb I2C Serial EEPROM, 400kHz | onsemi
The onsemi CAT24C04YI-GT3 is a 4-Kbit (512 x 8) I²C CMOS Serial EEPROM organized as 32 pages of 16 bytes each, supporting both Standard (100 kHz) and Fast (400 kHz) I²C protocols. Housed in an industrial-grade 8-pin TSSOP package, it operates from 1.8V to 5.5V with access time of 900 ns and provides 1,000,000 program/erase cycles endurance with 100-year data retention. A serial EEPROM is a non-volatile memory device accessed via a low-pin-count serial bus, used to store user-configurable parameters such as calibration data, device IDs, and configuration registers. The CAT24C04 sits in the EEPROM > non-volatile memory > memory IC > integrated circuit taxonomy, and serves as a compact, parameter-sensitive solution to embedded non-volatile storage needs. Key features include hardware write protection via the WP pin, software write protection through block-level access control, and 16-byte page write mode for efficient multi-byte programming. The device uses a self-timed write cycle and integrates noise suppression filters on the SCL/SDA inputs, eliminating the need for external RC components. It also supports hardware device address selection through the A0-A2 pins to support up to 8 devices on the same bus. The CAT24C04YI-GT3 uses CMOS technology with a 2-wire I²C serial interface compatible with industry-standard EEPROM protocols. The device addresses memory using a 2-byte address scheme with the two most significant bits embedded in the device address byte, allowing pin-to-pin compatibility with the smaller-density CAT24C02x. The wide VCC range (1.8V-5.5V) supports both 3.3V and 5V system designs without level shifting. Typical applications include consumer electronics configuration storage, industrial sensor calibration, IoT device parameter storage, white goods settings retention, smart meter data logging, and automotive infotainment non-volatile memory. The 8-pin TSSOP package is well-suited for compact PCB designs where board space is constrained. When designing with this EEPROM, ensure SDA/SCL pull-up resistors (2.2kΩ to 10kΩ depending on bus capacitance) are placed close to the bus master. Verify the total bus capacitance including all device pins remains below 400 pF for reliable Fast-mode operation at 400 kHz. This page synthesizes distributor pricing, drop-in alternatives across onsemi and competitor families, and practical design notes not found in the manufacturer datasheet.
DS2430AP+ - 256-Bit 1-Wire EEPROM, 6-TSOC | Analog Devices
The Analog Devices (formerly Maxim Integrated) DS2430AP+ is a 256-bit 1-Wire EEPROM organized as 32 bytes of user memory, housed in a 6-pin TSOC (6-LSOJ) surface-mount package measuring 3.76 mm in width. The device communicates over the Dallas/Maxim 1-Wire bus with a 15 µs time-slot bit rate and operates from 2.8 V to 5.25 V on a single data line plus ground, requiring only one microcontroller port pin for full interface. A 1-Wire EEPROM is a serial non-volatile memory that combines data storage, unique device identification, and power delivery on a single conductor. The DS2430AP+ belongs to the broader category of serial EEPROMs (EEPROM -> non-volatile memory -> memory IC -> semiconductor) and is widely used for board identification, calibration constants, and consumable authentication in embedded systems. Because the protocol also carries parasitic power, designers can mount the part on a PCB with only two pads (data + ground), which dramatically simplifies wiring. Key features include a factory-lasered 64-bit registration number (unique 48-bit serial number, 8-bit CRC, 8-bit family code 14h), 32 x 8-bit user-programmable EEPROM, an additional 64-bit OTP area for permanent write protection, and an on-chip 8-bit CRC generator. The EEPROM cells are rated for a minimum of 100,000 write cycles and 10 years of data retention at +85 °C. The device supports both parasitic-power mode (power harvested from the data line) and external-supply mode for write-heavy applications. The DS2430A family uses a strict master-slave timing protocol. Every bit transaction begins with the master pulling the line low for 15 µs; the slave samples in the middle of the slot. A strong pull-up (typically 2.2 kΩ–4.7 kΩ idle, switched to a few hundred ohms during EEPROM writes) is required in parasitic-power mode to supply the programming current. The on-chip CRC and unique 64-bit ROM ID allow multiple DS2430A devices to coexist on a single bus with guaranteed addressing. Typical applications include PCB identification and asset tracking, printer and consumable cartridge authentication, medical-device calibration storage, industrial sensor calibration constants, battery-pack telemetry tags, and accessory authentication for handheld instruments. Its single-wire interface is ideal when board space, connector pin count, or wiring harness complexity is constrained. When designing with the DS2430AP+, follow the manufacturer's 1-Wire timing guidelines, place the pull-up resistor close to the host pin, and use a strong pull-up during EEPROM write cycles in parasitic mode. Decoupling the data line with a small capacitor can improve noise immunity in long-cable applications. The "+" suffix indicates lead-free, RoHS-compliant packaging on tape and reel. This page synthesizes distributor pricing, drop-in alternatives in the same 6-TSOC package, and practical 1-Wire bus design notes that are not consolidated in the manufacturer datasheet — a useful information gain for engineers evaluating the DS2430AP+ for identification and authentication designs.
DS24B33+ - 4Kb 1-Wire EEPROM, TO-92 | Analog Devices
The Analog Devices / Maxim Integrated DS24B33+ is a 4096-bit (4 Kbit) 1-Wire® EEPROM organized as 16 memory pages of 256 bits each, packaged in a 3-pin TO-92 through-hole form factor. The device communicates over a single-conductor 1-Wire bus following the standard 1-Wire protocol, with each device carrying a factory-programmed, unalterable unique 64-bit registration number for multidrop addressing. A 1-Wire EEPROM is a non-volatile memory device that combines data storage with a one-wire serial communication interface pioneered by Dallas Semiconductor (now part of Analog Devices). Unlike I²C or SPI EEPROMs that require two or four signal lines, 1-Wire parts use only a single data line plus ground, allowing power and data to share the same conductor via parasitic power. Within the broader memory hierarchy, the DS24B33 sits in the EEPROM family (electrically erasable programmable read-only memory), which is a subset of non-volatile memory (NVM) and ultimately semiconductor memory ICs. Key features include 200K write/erase cycle endurance per page, a 32-byte scratchpad for verified data transfer, sixteen 32-byte pages of EEPROM, an on-chip CRC-16 generator for data transfer validation, and an operating voltage range of 2.8V to 5.25V. Data writes are protected by a strict read/write protocol that verifies the scratchpad contents against the master before committing to EEPROM, eliminating partial-write corruption. The DS24B33 is software- and pin-compatible with the legacy DS2433, providing a modern silicon replacement that uses newer semiconductor technology. The TO-92-3 package supports hand-up (uidance-style hand-solderable) installation in low-volume and field-deployed applications where surface-mount is impractical, such as outdoor sensor enclosures, automotive wiring harnesses, and access control tokens. Typical applications include PCB identification and authentication, consumable authentication (ink cartridges, medical sensors), access control iRODs (ibutton ID rings), environmental sensor calibration storage, inventory tracking, and iButton (button-style ID) accessories. The unique 64-bit ROM registration number enables 1-Wire multidrop networks where many devices share a single bus. A key design consideration is the requirement for a 4.7 kΩ pull-up resistor on the 1-Wire data line, plus proper ESD protection. For long cable runs, the strong pull-up during write/erase cycles and proper ground return are essential for reliable operation. This page synthesizes synthesizer-equipped manufacturer datasheet data, distributor stock, includes, applies, applies, design considerations and practical design notes not found in the manufacturer datasheet alone.
DS28E25P+T - 1-Wire SHA-256 Authenticator, 4Kb EEPROM, TSOC-6
The Analog Devices / Maxim Integrated DS28E25P+T is a DeepCover Secure Authenticator that combines a FIPS 180-3-compliant SHA-256 cryptographic engine with 4 Kbits (512 bytes) of user EEPROM in a 6-pin TSOC package. Housed in the compact 6-TSOC (0.148", 3.76 mm width) surface-mount package, the DS28E25P+T communicates over a single-wire Maxim 1-Wire bus and operates from a 3.0 V to 3.6 V single supply while parasitically drawing power from the data line when required. The "+T" suffix denotes tape-and-reel packaging. What is a Secure Authenticator? A secure authenticator is a specialized IC that stores a secret key in protected memory and performs a cryptographic challenge-response handshake with a host controller, allowing the host to verify that a peripheral (sensor, battery, accessory, or consumable) is genuine before granting access, transferring data, or activating functionality. Within the broader taxonomy, the DS28E25 sits in the hierarchy: secure authenticator -> authentication IC -> security IC -> semiconductor. Its DeepCover family designation indicates multilayer physical security protecting the on-chip secret key from invasive and non-invasive attack. The DS28E25 implements bidirectional SHA-256 challenge-and-response authentication using a 256-bit secret and a unique 64-bit ROM ID that is factory-lasered into each die. The device integrates an on-die SHA-256 accelerator and a 4 Kbit (512-byte) user EEPROM array partitioned into four 128-byte pages, with each page lockable to support write-protect-once, write-protect-permanently, and OTP/secret modes. Operating temperature spans -40 C to +85 C (industrial grade), and the part is rated for a typical 1-Wire pull-up of 2.2 kohm with strong ESD protection on the IO/data pin. The DS28E25 is widely used to authenticate medical sensors, batteries and chargers, printer cartridges, industrial sensors, and any peripheral whose authenticity directly affects safety, IP protection, or revenue. By placing an inexpensive DS28E25 on a consumable or accessory and storing a unique secret in its EEPROM, OEMs can deter cloning and gray-market substitution. Compared with software-only authentication, the DS28E25 places the secret inside a tamper-resistant IC, making key extraction materially harder. When laying out the PCB, keep the DQ/IO trace short and place a single 2.2 kohm pull-up to the host-side 1-Wire rail; avoid stubs and long parallel runs to other digital lines. Ensure the host GPIO used for the 1-Wire bus is open-drain capable, and budget for the 1-Wire reset/presence pulse timing as specified in the datasheet timing section.
DS28EC20+ - 20Kb 1-Wire EEPROM, TO-92-3 | Analog Devices
The Analog Devices DS28EC20+ is a 20480-bit (20 Kbit) 1-Wire EEPROM organized as 80 memory pages of 256 bits each, plus an additional 256-bit page reserved for control functions, and is delivered in a TO-92-3 through-hole package. It communicates over a single-contact 1-Wire interface at a standard speed of up to 15.4 kbps or an overdrive speed of up to 90 kbps, with the host supplying power parasitically through the same data line. According to the manufacturer datasheet (Revision 10), data is written via a 32-byte scratchpad, verified with a read-back, and finally copied to the EEPROM array, providing strong write-cycle integrity for embedded logging. A 1-Wire EEPROM is a serial non-volatile memory that combines data storage and communication on a single conductor plus ground, allowing multiple parts to share one bus and to be identified by a unique 64-bit ROM ID. The DS28EC20 belongs to the EEPROM -> non-volatile memory -> memory IC hierarchy within the broader semiconductor category, and it is one of the largest-density single-contact serial EEPROMs in the 1-Wire family, second only to higher-density siblings like the DS28CM00. Key features include a wide operating range from 2.8 V to 5.25 V on VPUP, an operating temperature of -40 °C to +85 °C, a write endurance of 200k cycles per door, and over 40 years of data retention. The DS28EC20 also provides a high degree of backward compatibility with the legacy DS2433, requiring only a lengthening of tPROG from 5 ms to 10 ms, making it a popular migration target for retrofit designs that need more memory than 4 Kbit-class 1-Wire parts can offer. The TO-92-3 footprint suits through-hole PCB assemblies and probe-style mechanical enclosures. The DS28EC20 uses a single-pin CMOS interface with internal parasitic-power charge-pump storage. The overdrive mode (4–5.25 V VPUP) enables faster factory programming and high-throughput identification, while standard mode supports long cable runs up to several meters. Its unique 64-bit ROM address and robust CRC-16 allow reliable device selection on a multidrop bus, simplifying firmware that needs to identify, authenticate, or store calibration data on a per-module basis. Typical applications include per-board identification and traceability in industrial control modules, calibration and configuration storage in sensor assemblies, accessory authentication in medical and test equipment, firmware/license key storage in embedded systems, and tamper-evident parameter logging in metering devices. The 20 Kbit capacity is sufficient for storing calibration curves, user settings, audit logs, or small lookup blocks. When migrating from DS2433 (4 Kbit) or DS2431 (1 Kbit), the DS28EC20 is a 5x-20x density upgrade on the same 1-Wire protocol. A key design tip is to add a 2.2 kΩ pull-up resistor on the 1-Wire data line to a regulated 3.3 V or 5 V rail (VPUP), and ensure your CRC-16 routine matches the device-generated polynomial so that multidrop bus contention is detected reliably. This page synthesizes distributor pricing, same-package alternatives, and practical design notes not found in the manufacturer datasheet, giving procurement and design engineers an at-a-glance engineering reference for the DS28EC20+.
DS28EC20P+ - 20Kb 1-Wire EEPROM | Analog Devices | TSOC-6
The Analog Devices (formerly Maxim Integrated) DS28EC20P+ is a 20-Kbit (20480-bit) 1-Wire EEPROM organized as 80 memory pages of 256 bits each, with an additional page reserved for control functions, housed in a 6-pin TSOC surface-mount package. The device operates from a single-contact 1-Wire serial interface that carries both data and parasitic supply, eliminating the need for an external power pin and enabling connection with a single data line plus ground return. A 1-Wire EEPROM is a type of non-volatile serial memory IC that combines data storage and communication over a single conductor using a vendor-specific signaling protocol, falling within the EEPROM memory hierarchy and broader memory product classification. Memories fall within the semiconductor IC hierarchy, which is part of the discrete and integrated semiconductor electronics stack. The 1-Wire interface is widely used in identification, calibration, accessory-authentication, and board-tagging applications because it minimizes wiring and allows multiple devices to share one bus. Key features of the DS28EC20P+ include a 32-byte scratchpad that verifies data before committing to EEPROM, page write capability of up to 32 bytes per write cycle, a unique 64-bit ROM ID for multi-drop bus addressing, an Overdrive mode that raises the bus speed up to 80 MHz equivalent for faster reads, and ESD protection rated per JEDEC HBM on the IO pin. The device derives its operating current parasitically from the 1-Wire line during communication, with the EEPROM page write current supplied from an external reservoir capacitor. The DS28EC20 architecture uses an addressable-cell decoder with a precision charge pump to program the floating-gate EEPROM cells, ensuring 200K write-cycle endurance and greater than 40-year data retention. Its robust ROM-SHA test structure enables 64-bit unique serialization across billions of devices, and the Overdrive Skip ROM command provides backward compatibility with standard-speed 1-Wire hosts when used on a single-drop bus. Typical applications include printed circuit board identification and traceability, sensor calibration data storage, medical device accessory authentication, industrial control module tagging, and consumable authentication in printers or analyzers. The device is designed for new designs per the manufacturer product page and is well-suited for both factory-floor automation and field-deployed equipment. When designing with this part, observe the 1-Wire timing requirements published in the device datasheet, choose a properly sized reservoir capacitor for EEPROM write currents, and consider ESD layout practices on the exposed single data line. The TSOC-6 package supports standard surface-mount reflow while keeping the wire-bond loop compact for reliable 1-Wire signaling. This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes not found in the manufacturer datasheet alone, and is intended as an engineering decision aid for sourcing and second-source planning.