Microchip Technology 34VL02/SN

Overview

34VL02 from Microchip Technology Inc. is a 2 Kbit (256 × 8) I²C-compatible serial EEPROM with dual software write-protection (SWP/PSWP) for addresses 00h–7Fh, hardware write-protect via WP pin, and operation down to 1.5 V. It delivers 1 mA typical read current, 100 nA standby current, and supports up to eight cascaded devices on one bus. Used in embedded system configuration storage where low-voltage operation and selective memory protection are critical.

For engineers reviewing the 34VL02 datasheet, 34VL02 pinout, 34VL02 application, or 34VL02 equivalent, key selection considerations include its 1.5–3.6 V supply range, 16-byte page write buffer, Schmitt-triggered SCL/SDA inputs, 400 kHz max clock (100 kHz below 1.8 V), and support for permanent or resettable lower-array write protection.

Technical Context

The 34VL02 implements a 2-wire I²C slave interface with addressable chip select (A0–A2), supporting both byte and page writes (up to 16 bytes per page). Its internal architecture includes a high-voltage detection circuit on A0 for SWP/CSWP/PSWP command execution and a threshold-based VCC detector that disables erase/write logic below 1.35 V.

Write protection operates at three levels: hardware (WP pin tied to VCC locks full 256-byte array), resettable software (SWP/CSWP commands protect 00h–7Fh), and permanent software (PSWP command irreversibly locks 00h–7Fh). Acknowledge polling enables bus efficiency during write cycles, which self-time to ≤5 ms.

Key Specifications

Pinout & Package

Available in 8-lead PDIP, SOIC, TSSOP, MSOP, TDFN, and 6-lead SOT-23 packages. Pin functions are consistent across all 8-lead variants; SOT-23 omits A2 and WP pins (NC).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C02C-SSHM-T and BR24G02-3MNUC, the 34VL02 uniquely combines 1.5 V minimum operation, permanent software write-protection, and VCC brown-out write inhibition-making it the only option for safety-critical, battery-constrained, or ultra-low-voltage systems requiring guaranteed memory integrity.

Availability

34VL02 is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, smart energy meter firmware patching, automotive body control module settings, and embedded system boot parameter storage requiring stable component supply across extended product lifecycles.

Supply support for 34VL02 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 34VL02 belongs to Microchip's low-voltage serial EEPROM product line, engineered specifically for battery-powered, energy-efficient, and safety-conscious embedded systems where memory integrity at sub-1.8 V operation is mandatory.

FAQ

What is the minimum operating voltage for the 34VL02, and how does it affect write functionality?

The 34VL02 operates down to 1.5 V, with full read/write functionality maintained across the 1.5–3.6 V range. Its internal VCC threshold detector disables erase/write logic below 1.35 V to prevent data corruption during brown-out conditions. This ensures that the 34VL02 will not execute any write or erase command when supply voltage drops into an unreliable region, preserving memory integrity even during unstable power transitions.

How does the Permanent Software Write-Protect (PSWP) feature work on the 34VL02, and can it be reversed?

The PSWP feature on the 34VL02 is activated by applying a high-voltage pulse to the A0 pin while issuing a specific command sequence (Device Type Identifier '0110' with correct A1/A2 levels). Once executed, PSWP permanently locks addresses 00h–7Fh against all write attempts-including power cycling, WP pin state changes, or subsequent software commands. The 34VL02 will no longer acknowledge the '0110' identifier after PSWP activation, confirming irreversible protection.

Can the 34VL02 be used in a 400 kHz I²C system powered at 1.7 V?

No-the 34VL02 supports 400 kHz operation only when VCC ≥ 1.8 V. At 1.7 V, the maximum clock frequency is limited to 100 kHz per datasheet Table 1-2. Attempting 400 kHz communication at 1.7 V violates AC timing specifications (e.g., THIGH, TLOW, TR/TF), risking bus arbitration failure, missed ACKs, or incomplete writes. System designers must either raise VCC to ≥1.8 V or configure the master to enforce 100 kHz mode below that threshold.

What is the purpose of the A0 pin beyond chip addressing in the 34VL02?

In addition to serving as a chip-select bit (A0), the A0 pin on the 34VL02 functions as a high-voltage detect input for executing SWP, CSWP, and PSWP commands. When VHV (7–10 V, depending on VCC) is applied to A0 during these command sequences, the internal high-voltage generator activates to program the write-protect register or fuse. This dual-role design eliminates the need for external HV circuitry while maintaining secure, voltage-gated access to protection features.

Does the 34VL02 support sequential reads across multiple devices on the same I²C bus?

No-the 34VL02 does not support sequential reads across device boundaries. While up to eight 34VL02 devices can share one I²C bus using A2–A0 for addressing, the internal Address Pointer resets upon each device selection. A sequential read initiated on Device A will not continue into Device B's memory space. To access contiguous 16 Kbit blocks, software must manage discrete reads per device using explicit addressing, as described in Section 6.4 of the datasheet.