Microchip Technology AT24C64A-10TU-2.7-T

Overview

AT24C64A-10TU-2.7-T from Microchip Technology (formerly Atmel) is a 64 Kbit (8192 × 8) two-wire serial EEPROM with I²C-compatible interface, operating from 2.7V to 5.5V, featuring hardware write protection via WP pin, 32-byte page write capability, and 1 million write cycles endurance. It is used for nonvolatile parameter storage in embedded controllers, power supply monitors, and industrial sensor nodes.

For engineers reviewing the AT24C64A-10TU-2.7-T datasheet, AT24C64A-10TU-2.7-T pinout, AT24C64A-10TU-2.7-T application, or AT24C64A-10TU-2.7-T equivalent, key selection criteria include VCC range compatibility (2.7–5.5 V), TSSOP-8 package footprint, 400 kHz I²C speed at 2.7 V, WP-enabled hardware data protection, and industrial temperature rating (–40°C to +85°C).

Technical Context

The AT24C64A-10TU-2.7-T implements a standard two-wire (I²C) serial interface with open-drain SDA and Schmitt-triggered SCL inputs for noise immunity. Addressing uses three hardware pins (A0–A2), enabling up to eight devices on one bus. Internal address counter supports current-address, random-address, and sequential read modes.

Write operations support byte and 32-byte page modes with self-timed internal write cycle (≤5 ms). Standby current is 2.0 µA at 2.7 V, and input leakage remains ≤3.0 µA across –40°C to +85°C. The device uses EEPROM cell technology with 100-year data retention and no external refresh required.

Key Specifications

Pinout & Package

AT24C64A-10TU-2.7-T is housed in an 8-lead TSSOP (Thin Shrink Small Outline Package) with 4.4 mm body width, 0.65 mm lead pitch, and RoHS-compliant lead finish. Pin 1 is marked by a notch or dot; package meets JEDEC MO-153, Variation AA.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C64A-10TU-2.7-T, AT24C64D-SSHM-T extends voltage range downward and improves ESD tolerance, while BR24G64FJ-WE2 reduces standby current and raises I²C speed ceiling-both require validation of WP pin behavior and page write timing in existing firmware.

Availability

AT24C64A-10TU-2.7-T is available at Aetrix Electronics and suitable for smart metering, industrial PLC modules, medical infusion pumps, and automotive body control applications requiring stable component supply across extended product lifecycles.

Supply support for AT24C64A-10TU-2.7-T 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 is a global semiconductor company specializing in microcontrollers, analog devices, and memory solutions, with broad industrial and automotive qualification capabilities.

The AT24C64A-10TU-2.7-T belongs to Microchip's legacy AT24Cxx serial EEPROM family, designed for cost-sensitive, low-power embedded systems requiring reliable nonvolatile storage with minimal board space and I²C bus simplicity.

FAQ

What is the maximum I²C clock frequency supported by the AT24C64A-10TU-2.7-T at 2.7 V?

The AT24C64A-10TU-2.7-T supports up to 400 kHz I²C clock frequency when operated at 2.7 V, as specified in Table 4 of the datasheet. This aligns with standard-mode I²C timing and ensures interoperability with legacy microcontrollers without requiring high-speed mode support. Exceeding this frequency may result in ACK failures or data corruption.

Does the AT24C64A-10TU-2.7-T require external pull-up resistors on SDA and SCL lines?

Yes, the AT24C64A-10TU-2.7-T requires external pull-up resistors on both SDA and SCL lines because its I/O pins are open-drain. Typical values range from 2.2 kΩ to 10 kΩ depending on bus capacitance and speed; 4.7 kΩ is commonly used for 400 kHz operation with ≤400 pF total bus capacitance. The AT24C64A-10TU-2.7-T itself does not integrate internal pull-ups.

How many devices can share the same I²C bus with the AT24C64A-10TU-2.7-T?

Up to eight AT24C64A-10TU-2.7-T devices can share a single I²C bus using the A0, A1, and A2 address pins. Each combination of hardwired high/low states sets a unique 3-bit device address, yielding addresses 0x50 through 0x57. Floating address pins default to logic low, so unconnected devices will all respond to 0x50 unless externally configured.

What happens to the AT24C64A-10TU-2.7-T when the WP pin is left unconnected?

When the WP pin of the AT24C64A-10TU-2.7-T is left floating, it is internally pulled down to GND via proprietary biasing circuitry-enabling normal write operations. However, Microchip recommends tying WP to GND explicitly if write protection is not needed, as capacitive coupling >3 pF to the VCC plane may cause unintended high-state activation and accidental write inhibition.

Is the AT24C64A-10TU-2.7-T qualified for automotive applications?

No, the AT24C64A-10TU-2.7-T is specified for industrial temperature range (–40°C to +85°C) and is not AEC-Q200 qualified. While it may function in some automotive environments, Microchip explicitly states in the datasheet disclaimer that "Atmel's products are not intended, authorized, or warranted for use as components in applications intended to support or sustain life." For automotive use, consider the AT24C64D-SSHM-T or BR24G64FJ-WE2 with formal AEC-Q200 certification.