STMicroelectronics ST25DV02K-W2R8T3

Overview

ST25DV02K-W2R8T3 from STMicroelectronics is a dynamic NFC/RFID tag IC compliant with ISO/IEC 15693 and NFC Forum Type 5, integrating two independent PWM outputs (PWM1 and PWM2), 2-Kbit EEPROM, on-chip 28.5 pF tuning capacitance, and TruST25 digital signature authentication. It operates with dual power domains: RF interface powered solely by the carrier field, and PWM interface powered by an independent 1.8–5.5 V DC supply (VCC/VSS), enabling standalone PWM operation without RF field presence. Used in smart sensors, industrial calibration tags, and contactless-adjustable LED drivers.

For engineers reviewing the ST25DV02K-W2R8T3 datasheet, ST25DV02K-W2R8T3 pinout, ST25DV02K-W2R8T3 application, or ST25DV02K-W2R8T3 equivalent, key selection considerations include dual-PWM configurability via RF, ±10% frequency accuracy over temperature, 62.5 ns pulse width resolution, password-protected memory segmentation (AREA0–AREA2 + PWM_CTRL), and coexistence modes between RF commands and active PWM outputs.

Technical Context

The device implements a dual-interface architecture: the analog front-end handles ISO/IEC 15693 RF communication using internal 28.5 pF tuning capacitance and supports all sub-carrier modes and data rates up to 53 kbps; the digital unit manages EEPROM access, PWM register updates, and TruST25 signature generation. PWM control registers (PWM1_CTRL at block F8h, PWM2_CTRL at F9h) are write-protected by dedicated 32-bit passwords and reside in a fixed-address user area.

PWM generation uses an internal oscillator with resolution scaling from 15-bit (488 Hz) to 9-bit (31.25 kHz), enabling precise duty-cycle control across seven frequency decades. Coexistence is managed via PWM_CFG register bits [6:4], allowing HiZ, ¼-power, or low-frequency PWM operation during RF command execution - configurable per application noise/power constraints.

Key Specifications

Pinout & Package

ST25DV02K-W2R8T3 is available in RoHS-compliant SO8N and TSSOP8 packages (ECOPACK2). Pin functions are identical across both packages.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dynamic NFC tag with PWM output applications.

Compared with ST25DV02K-W2R8T3, the W1 variant reduces pin count and simplifies register management but sacrifices independent second-channel control; the NTAG I2C Plus shifts PWM responsibility to host firmware, increasing BOM and software overhead while offering broader I²C ecosystem compatibility.

Availability

ST25DV02K-W2R8T3 is available at Aetrix Electronics and suitable for smart sensor calibration, contactless lighting control, and medical parameter tagging requiring stable component supply, long-term EEPROM reliability, and field-updatable PWM behavior.

Supply support for ST25DV02K-W2R8T3 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power management ICs, sensors, and connectivity solutions for industrial, automotive, and consumer markets.

The ST25DV series targets contactless configuration and monitoring applications, combining NFC/RFID functionality with integrated analog peripherals like PWM to eliminate host MCUs in simple actuation systems.

FAQ

What is the maximum PWM frequency and corresponding resolution?

The ST25DV02K-W2R8T3 supports PWM frequencies from 488 Hz to 31.25 kHz. At 31.25 kHz, resolution is 9-bit (512–32767 period range × 62.5 ns step = 32–2048 µs period), yielding 9-bit pulse width control. At 488 Hz, resolution scales to 15-bit for fine-grained duty-cycle adjustment. This scaling ensures full 0–100% duty cycle coverage across the entire frequency range.

How does the dual-power-domain architecture affect system design?

The RF interface operates solely from the 13.56 MHz carrier field, while PWM outputs require a separate 1.8–5.5 V DC supply on VCC/VSS. This allows PWM to run continuously during RF inactivity (e.g., driving LEDs while awaiting NFC commands) and enables RF access even when VCC is unpowered (e.g., reading stored calibration data from a battery-less tag). Decoupling capacitors (10 nF + 100 pF) must be placed near VCC/VSS pins to stabilize PWM operation.

Can PWM parameters be updated while the RF interface is active?

Yes - PWM parameters stored in blocks F8h (PWM1_CTRL) and F9h (PWM2_CTRL) can be updated live via ISO/IEC 15693 Write Single Block commands while RF is active. However, the PWM_CFG register defines coexistence behavior: setting bits [6:4] to "1xx" forces PWM outputs into high-impedance during RF command execution, ensuring no interference with RF demodulation. This mode is recommended for noise-sensitive environments.

What security mechanisms protect the PWM control registers?

PWM control registers (F8h/F9h) reside in the dedicated PWM_CTRL memory area, protected by a 32-bit password (PWD_PWM) and access rights defined in the APSA register. Write access requires opening a security session with PWD_PWM and verifying APSA permissions. Additionally, TruST25 digital signatures authenticate parameter updates, and the LOCK_BLOCK register can permanently lock PWM_CTRL blocks to prevent further modifications after commissioning.