Microchip Technology 24LC512T-I/ST14

Overview

24LC512T-I/ST14 from Microchip Technology Inc. is a 512 Kbit (64K × 8) I²C-compatible serial EEPROM with industrial temperature range (−40°C to +85°C), 2.5–5.5 V supply, 400 kHz max clock frequency, and 128-byte page write buffer. It features hardware write-protection via the WP pin, Schmitt-trigger inputs for noise immunity, and supports up to eight devices on a single I²C bus in embedded control and data-logging systems.

For engineers reviewing the 24LC512T-I/ST14 datasheet, 24LC512T-I/ST14 pinout, 24LC512T-I/ST14 application, or 24LC512T-I/ST14 equivalent, key selection criteria include its 2.5 V minimum operating voltage, 1 µA standby current, 5 ms max page write time, I²C address configuration via A0–A2 pins, and 14-lead TSSOP package compatibility with space-constrained industrial PCBs.

Technical Context

The 24LC512T-I/ST14 implements a two-wire I²C interface with open-drain SDA/SCL lines requiring external pull-ups, and uses internal address pointer logic for sequential, random, and current-address read modes. Its memory array is organized as a single 64K × 8 block with automatic address roll-over at FFFF_H.

Write operations are self-timed and support byte or page writes (up to 128 bytes); page boundaries are fixed at 128-byte intervals, and crossing them causes wraparound. The WP pin enables full-array hardware write-protection when tied to V_CC, and Schmitt-trigger inputs on SDA/SCL provide 50 ns spike suppression and hysteresis of 0.05 V_CC.

Key Specifications

Pinout & Package

24LC512T-I/ST14 is packaged in a 14-lead Thin Shrink Small Outline Package (TSSOP), with 0.65 mm lead pitch and exposed pad option (not electrically connected by default). Pin 1 is marked with a dot; pins 9–14 are NC (no connect) and must be left unconnected.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC512T-I/ST14, the 24AA512-I/ST14 offers broader voltage flexibility but identical timing and packaging, while the AT24C512BN-SH-T provides vendor diversity at the cost of address and write-protection implementation differences - both require layout-compatible placement but firmware validation.

Availability

24LC512T-I/ST14 is available at Aetrix Electronics and suitable for industrial sensor calibration storage, medical device configuration memory, automotive body control module settings, and smart energy meter firmware patch storage requiring stable component supply and long-term obsolescence management.

Supply support for 24LC512T-I/ST14 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 microcontroller, analog, FPGA, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing infrastructure.

The 24LC512 belongs to Microchip's 24XX512 family of I²C serial EEPROMs, designed specifically for reliable, low-power nonvolatile data storage in space-constrained industrial, medical, and automotive applications.

FAQ

What is the minimum supply voltage required for reliable operation of the 24LC512T-I/ST14?

The 24LC512T-I/ST14 requires a minimum supply voltage of 2.5 V for guaranteed operation across its full industrial temperature range (−40°C to +85°C). Unlike the 24AA512 variant, it is not specified for operation below 2.5 V - attempting to power the 24LC512T-I/ST14 at 1.8 V or lower may result in undefined behavior, failed writes, or I²C communication timeouts. Always verify regulator output stability under load and transient conditions.

Does the 24LC512T-I/ST14 support 1 MHz I²C clock speed?

No, the 24LC512T-I/ST14 does not support 1 MHz I²C clock speed. Its maximum rated clock frequency is 400 kHz at V_CC ≥ 2.5 V. The 1 MHz capability is exclusive to the 24FC512 variant within the same family. Using 1 MHz with the 24LC512T-I/ST14 will violate AC timing specifications (e.g., THIGH, TLOW, TR/TF), causing ACK failures, data corruption, or bus lockup - confirmed by DS20001754Q Table 1-2.

How many devices can be connected to the same I²C bus using the 24LC512T-I/ST14?

Up to eight 24LC512T-I/ST14 devices can be connected to a single I²C bus using unique combinations of the A0, A1, and A2 address pins. Each pin must be hardwired to either V_SS or V_CC to generate a distinct 3-bit chip address (1010xxxR/W), enabling individual addressing without external multiplexing. All eight positions are usable because the base I²C address '1010' occupies the upper four bits, leaving three bits for device selection.

What happens if a page write crosses a 128-byte boundary on the 24LC512T-I/ST14?

If a page write command attempts to cross a 128-byte physical page boundary on the 24LC512T-I/ST14, the address counter wraps around to the start of the same page instead of advancing to the next page. This causes newly transmitted bytes to overwrite earlier bytes within that 128-byte block. The datasheet explicitly warns against this behavior (DS20001754Q, Section 6.3), requiring firmware to split writes at page boundaries - a critical constraint for reliable data logging implementations.

Is the WP pin on the 24LC512T-I/ST14 sampled continuously or only at specific times?

The WP pin on the 24LC512T-I/ST14 is sampled only at the STOP condition of each write command - not continuously. If WP is pulled high *after* the STOP bit but before the internal write cycle completes, the ongoing write proceeds unhindered. This edge-triggered sampling ensures deterministic protection: write inhibition is evaluated once per command, preventing mid-cycle toggling from disrupting active programming. This behavior is documented in DS20001754Q Section 6.3 and Figure 1-1.