Microchip Technology 24AA515-I/P

Overview

24AA515-I/P from Microchip Technology Inc. is a 64K × 8 (512 Kbit) I²C-compatible serial EEPROM with 1.7–5.5 V operation, 400 kHz max clock frequency (100 kHz below 2.5 V), and industrial temperature range (–40°C to +85°C). It features 64-byte page write buffer, hardware write protection via WP pin, and Schmitt-trigger inputs for noise immunity - deployed in embedded system configuration storage and sensor calibration data retention.

For engineers reviewing the 24AA515-I/P datasheet, 24AA515-I/P pinout, 24AA515-I/P application, or 24AA515-I/P equivalent, key selection considerations include low-voltage operation down to 1.7 V, 1 million erase/write cycles, 200-year data retention, cascading support for up to four devices on one bus, and PDIP-8 packaging with through-hole mounting compatibility.

Technical Context

The 24AA515-I/P implements a two-wire I²C interface with slave address decoding using A0/A1 pins and mandatory A2 tied to VCC. Its internal architecture includes a 64-byte page latch, HV generator for EEPROM programming, and dual 256 Kbit memory segments accessed via block-select bit B0 in the control byte.

It supports byte and page writes with self-timed 5 ms max write cycle, acknowledge polling for bus efficiency, and sequential reads across 0000h–7FFFh and 8000h–FFFFh boundaries. Write protection is hardware-enforced by the WP pin, sampled at Stop condition, and independent of software control.

Key Specifications

Pinout & Package

24AA515-I/P is housed in an 8-lead plastic dual in-line package (PDIP) with 0.3 inch body width, suitable for through-hole PCB assembly and prototyping. Pin 1 is marked with a notch or dot; pin numbering follows standard DIP convention (counterclockwise from notch).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC515-I/P, the 24AA515-I/P enables lower-voltage operation but shares identical functionality above 2.5 V; versus AT24C512-10PU-2.7, it offers superior bus scalability and 1.7 V compatibility at the cost of PDIP-8 packaging and A2 pin constraint.

Availability

24AA515-I/P is available at Aetrix Electronics and suitable for industrial sensor nodes, medical device calibration storage, and smart energy metering requiring stable component supply, long-lifecycle support, and RoHS-compliant through-hole assembly.

Supply support for 24AA515-I/P 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 U.S.-based semiconductor manufacturer specializing in microcontrollers, analog devices, and nonvolatile memory solutions for embedded control applications.

The 24AA515-I/P belongs to Microchip's 24XX515 family of I²C EEPROMs, designed specifically for low-power, wide-voltage-range data storage in portable, industrial, and automotive systems where reliability and ease of integration are critical.

FAQ

What is the minimum supply voltage required for reliable operation of the 24AA515-I/P?

The 24AA515-I/P operates reliably down to 1.7 V, making it compatible with 1.8 V logic systems without level translation. Below 2.5 V, maximum I²C clock frequency is limited to 100 kHz to ensure timing margin. This specification is validated across the full industrial temperature range (–40°C to +85°C) and is documented in DS21673G, Table 1-1.

How does the A2 pin function on the 24AA515-I/P, and what happens if it is left unconnected?

The A2 pin on the 24AA515-I/P is a non-configurable chip select that must be hard-wired to VCC for device operation. If left floating or tied to VSS, the 24AA515-I/P will not respond to I²C commands or acknowledge addresses. This design prevents unintended activation and is explicitly stated in DS21673G, Section 2.2 and Table 2-1.

Can the 24AA515-I/P perform sequential reads across its entire 64K address space without interruption?

No - sequential reads on the 24AA515-I/P are limited to two 32K-byte blocks: 0000h–7FFFh and 8000h–FFFFh. Crossing either boundary causes automatic address roll-over (e.g., reading past 7FFFh returns data from 0000h). To read full memory, software must issue separate read commands for each block, as defined in DS21673G, Section 8.3.

What is the purpose of the WP pin on the 24AA515-I/P, and when is its state sampled?

The WP (Write-Protect) pin on the 24AA515-I/P disables all write operations when held high (VCC). Its logic state is sampled only at the Stop condition of each write command - toggling WP during an active write cycle has no effect. This ensures deterministic protection behavior and is detailed in DS21673G, Section 6.3 and Figure 1-1.

Does the 24AA515-I/P support page writes across physical page boundaries, and what occurs if attempted?

No - page writes on the 24AA515-I/P are restricted to within a single 64-byte physical page. Attempting to write across a boundary (e.g., starting at address 0x003F and writing 64 bytes) causes wraparound: data beyond the page end overwrites the start of the same page. Application firmware must enforce page-aligned writes, as specified in DS21673G, Section 6.2 note.