Microchip Technology 34LC02T-E/ST

Overview

34LC02T-E/ST from Microchip Technology Inc. is a 2 Kbit I²C-compatible serial EEPROM with hardware and dual software write-protection, 1 MHz clock support (V_CC ≥ 2.5 V), 16-byte page buffer, and operation down to 2.2 V. It delivers 100 nA standby current and >1 million erase/write cycles, deployed in automotive body control modules for storing calibration data and configuration settings.

For engineers reviewing the 34LC02T-E/ST datasheet, 34LC02T-E/ST pinout, 34LC02T-E/ST application, or 34LC02T-E/ST equivalent, key selection factors include its 1 MHz I²C timing compliance at 2.5–5.5 V, SOT-23-6 package footprint, WP pin-based full-array hardware protection, and permanent/resetttable lower-half (00h–7Fh) software write-protect capability.

Technical Context

The 34LC02T-E/ST implements a 2-wire I²C slave interface with Schmitt-trigger inputs and slope-controlled outputs to suppress noise and eliminate ground bounce. Its memory array is organized as 256 × 8-bit with an internal address pointer supporting current-address, random, and sequential reads.

Write operations include byte-write and 16-byte page-write modes with self-timed erase/write cycles (5 ms max). Write protection is enforced via three independent mechanisms: external WP pin (full-array), resettable SWP command (lower 128 bytes), and permanent PSWP command (lower 128 bytes), all validated under -40°C to +125°C automotive temperature range.

Key Specifications

Pinout & Package

34LC02T-E/ST is housed in a Pb-free, RoHS-compliant 6-lead SOT-23 package (3.0 mm × 1.7 mm × 1.3 mm), optimized for space-constrained automotive PCBs. A2 and WP pins are not connected (NC) in this variant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C02D-SSHM-T and BR24G02-3MNUX, the 34LC02T-E/ST uniquely combines automotive-grade temperature rating (-40°C to +125°C), permanent software write-protection (PSWP), and hardware WP pin in a 6-pin SOT-23 package - making it the only option qualified for safety-critical automotive memory applications requiring layered, irreversible protection.

Availability

34LC02T-E/ST is available at Aetrix Electronics and suitable for automotive electronics, industrial sensor calibration, and medical device configuration storage requiring stable component supply across extended lifecycles.

Supply support for 34LC02T-E/ST 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 34LC02T-E/ST belongs to Microchip's 34XX02 family of I²C EEPROMs, engineered specifically for automotive and industrial applications demanding robust write-protection, extended temperature operation, and low-power nonvolatile storage.

FAQ

What is the maximum I²C clock frequency supported by the 34LC02T-E/ST?

The 34LC02T-E/ST supports up to 1 MHz I²C clock frequency when V_CC is 2.5 V or higher. At V_CC < 2.5 V, the maximum clock rate drops to 400 kHz. This specification is explicitly defined in the Device Selection Table and AC Characteristics section of the DS22029F datasheet, and applies directly to the 34LC02T-E/ST variant.

Does the 34LC02T-E/ST have hardware write protection, and how is it implemented?

Yes, the 34LC02T-E/ST includes hardware write protection via the WP pin: when tied to V_CC, the entire memory array (00h–FFh) is write-protected; when tied to V_SS, protection is disabled. This function operates independently of software write-protection states and remains active across power cycles - a confirmed feature documented in Section 7.1 and Pin Function Table of DS22029F.

What package type is used for the 34LC02T-E/ST, and are all pins functional?

The 34LC02T-E/ST uses a 6-lead SOT-23 package. Per the Pin Function Table (DS22029F, page 14), pins A2 and WP are not connected (NC) in this variant. Functional pins are SCL (1), VSS (2), SDA (3), A1 (4), A0 (5), and VCC (6). This mapping is confirmed in both the package diagram and marking information sections of the datasheet.

How does the permanent software write-protect (PSWP) feature work on the 34LC02T-E/ST?

The PSWP command permanently locks addresses 00h–7Fh against all future writes, regardless of WP pin state or power cycling. Once executed, the device no longer acknowledges the '0110' device identifier used for write-protect commands. This irreversible behavior is verified in Table 7-1 and Section 7.3 of DS22029F and applies identically to the 34LC02T-E/ST.

What is the endurance and data retention specification for the 34LC02T-E/ST?

The 34LC02T-E/ST guarantees more than 1 million erase/write cycles and data retention exceeding 200 years at 25°C. These values are specified in the Features list (page 1) and Electrical Characteristics (Table 1-2, Note 4) of DS22029F, and are validated for the automotive temperature grade (E-temp) of the 34LC02T-E/ST.