STMicroelectronics ST25R100-CMET

Overview

ST25R100-CMET from STMicroelectronics is a high-performance NFC/HF RFID reader IC supporting ISO14443A/B, ISO15693, and NFC Forum T1T–T5T protocols at up to 106 kbit/s, with 256-byte FIFO, dynamic power output (DPO), and inductive wake-up for low-power card detection. It operates from 2.7–5.5 V, delivers up to 6 V_P antenna drive, and integrates regulators for PSRR optimization in compact consumer and industrial NFC interfaces.

For engineers reviewing the ST25R100-CMET datasheet, ST25R100-CMET pinout, ST25R100-CMET application, or ST25R100-CMET equivalent, this transceiver enables robust contactless interaction in space-constrained designs requiring multi-protocol support, high sensitivity in noisy environments, dual-antenna flexibility, and precise analog front-end control for tag reading and custom protocol implementation.

Technical Context

The ST25R100 implements a dual-path analog front end with independent RFI1/RFI2 receiver inputs and RFO1/RFO2 transmitter outputs, supporting differential, single-ended, or two independent single-ended antenna configurations. Its noise suppression receiver (NSR) technology and automatic gain control + squelch maximize SNR in electrically noisy settings.

It features a 27.12 MHz quartz oscillator with fast-start biasing and stability monitoring via I_osc interrupt, plus an auxiliary 26.48 kHz RC oscillator dedicated to wake-up timer operation-enabling sub-100 µA inductive wake-up mode with periodic antenna property scanning and IRQ-triggered tag approach/removal detection.

Key Specifications

Pinout & Package

ST25R100-CMET is housed in a 4×4 mm UFQFPN24 (ECOPACK2-compliant) package with exposed thermal pad (VSS/EP). Pin assignment is validated per DS14139 Rev 5, Figure 2 and Table 1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NFC reader applications.

Compared with PN7160 and SLI13, the ST25R100-CMET uniquely combines dual-antenna capability, ISO15693 support, inductive wake-up, and integrated regulators-making it optimal for industrial and appliance applications demanding robustness, flexibility, and low-power responsiveness.

Availability

ST25R100-CMET is available at Aetrix Electronics and suitable for healthcare device pairing, smart appliance parameter setup, and industrial tool authentication requiring stable component supply, long-term lifecycle assurance, and compliance with ECOPACK2 environmental standards.

Supply support for ST25R100-CMET 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 automotive, industrial, and consumer markets.

The ST25 family targets NFC and HF RFID system integration, with the ST25R100 specifically engineered for high-reliability, multi-protocol reader applications in electrically noisy, space-constrained, and battery-sensitive environments.

FAQ

What antenna configurations does the ST25R100-CMET support?

The ST25R100-CMET supports three antenna topologies: differential (RFO1+RFO2 driving one antenna), single-ended (RFO1 or RFO2 individually driving one antenna), and dual single-ended (RFO1 and RFO2 simultaneously driving two independent antennas). Each configuration uses the same RFI1/RFI2 receiver path and requires appropriate EMC filtering per DS14139 Figures 3–5.

How does the inductive wake-up mode reduce power consumption?

In inductive wake-up mode, the ST25R100-CMET disables its 27.12 MHz crystal oscillator and main regulators, relying solely on its 26.48 kHz RC oscillator and wake-up timer to periodically sample antenna impedance. This reduces typical current draw to under 100 µA while maintaining detection of nearby NFC tags or devices-ideal for battery-powered systems needing instant responsiveness without continuous power drain.

Can the ST25R100-CMET interface directly with a 1.8 V microcontroller?

Yes-the ST25R100-CMET's VDD_IO pin accepts 1.65–5.5 V, allowing direct SPI interfacing with 1.8 V MCUs. Level shifters isolate the internal 1 V digital core (VDD_D) and 3 V analog domain (VDD_A) from VDD_IO, ensuring reliable communication without external translation circuitry. The BSS, MOSI, SCLK, and IRQ pins are all compatible with 1.8 V logic levels when VDD_IO = 1.8 V.

What is the purpose of the AGD pin and how should it be decoupled?

The AGD pin provides the analog reference voltage (typically ~1.2 V) for internal ADCs and bias circuits. It must be decoupled with a 1 µF capacitor in parallel with a 10 nF capacitor, connected directly to GND_A (pin 18). Improper decoupling causes instability in receiver gain control and antenna tuning measurements, degrading SNR and read range-especially critical in multi-protocol or noisy EMI environments.