Microchip Technology 34VL02/ST

Overview

34VL02 from Microchip Technology Inc. is a 2 Kbit (256 × 8) I²C-compatible serial EEPROM with dual software write-protect (SWP/PSWP) for addresses 00h–7Fh, hardware write-protection via WP pin, and operation down to 1.5V. It delivers 1 mA typical read current, 100 nA standby current, and supports up to eight cascaded devices on one bus. It is used in embedded systems requiring nonvolatile parameter storage with flexible protection schemes, such as industrial sensor calibration or power-management configuration.

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 SDA/SCL inputs for noise immunity, 400 kHz max clock (100 kHz below 1.8 V), and support for both permanent and resettable lower-array write protection.

Technical Context

The 34VL02 implements a standard I²C slave interface with addressable 256-byte memory organized as one block, using A0–A2 for device addressing (up to eight devices per bus). Its internal control logic handles byte and page writes with self-timed erase/write cycles, and includes dedicated high-voltage detection on A0 for SWP/CSWP command validation.

Write protection is implemented at three levels: hardware (WP pin tied to VCC locks full 00h–FFh array), resettable software (SWP/CSWP commands protect 00h–7Fh), and permanent software (PSWP command irreversibly locks 00h–7Fh). All protection modes coexist and are evaluated before acknowledging write attempts.

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.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C02C-SSHM-T and BR24G02FJ-WE2, the 34VL02 uniquely combines permanent (PSWP), resettable (SWP), and hardware (WP) write protection in a single 1.5 V–capable device - enabling three-tiered data security without external components or firmware overhead.

Availability

34VL02 is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, automotive body control modules, and energy meter firmware patch 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 devices, 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, designed specifically for energy-constrained and safety-critical applications where flexible, multi-layer write protection and ultra-low standby current are essential.

FAQ

What is the minimum operating voltage for the 34VL02?

The 34VL02 operates down to 1.5 V, enabling direct integration with sub-1.8 V logic families and battery-powered systems. Below 1.8 V, maximum I²C clock frequency is limited to 100 kHz to maintain timing margins. This low-voltage capability eliminates the need for voltage translators in many portable and energy-harvesting designs.

How does hardware write protection work on the 34VL02?

Hardware write protection on the 34VL02 is controlled by the WP pin: tying WP to VCC disables all write operations to the full 256-byte array (00h–FFh), regardless of software protection state; tying WP to VSS disables hardware protection, allowing writes subject to software rules. This provides a fail-safe physical lock independent of firmware execution.

Can the 34VL02 be used in cascaded I²C configurations?

Yes, the 34VL02 supports cascading up to eight devices on a single I²C bus using the A0, A1, and A2 address pins. Each device is selected by matching its external A2–A0 logic levels to the corresponding bits in the I²C slave address, enabling scalable memory expansion without additional address decoding logic.

What is the purpose of the A0 pin beyond chip addressing?

In addition to serving as an address input, the A0 pin on the 34VL02 detects high-voltage (VHV) during SWP and CSWP command execution. When VHV (7–10 V depending on VCC) is applied to A0, the device validates the special '0110' device identifier and executes the software write-protect instruction - providing tamper-resistant configuration locking.

Does the 34VL02 support page write operations, and what is the buffer size?

Yes, the 34VL02 supports page write operations with a 16-byte internal buffer. Up to 16 bytes can be loaded sequentially before issuing a Stop condition, after which the device performs a self-timed internal write cycle. Writes crossing physical page boundaries (every 16 bytes) wrap within the current page, requiring firmware to manage alignment.