STMicroelectronics RX95HF-VMD5T

Overview

RX95HF-VMD5T from STMicroelectronics is a near field communication (NFC) transceiver IC designed for ISO/IEC 14443 Type A tag emulation in passive peer-to-peer mode. It integrates a dedicated analog front end (AFE), internal frame controller, and field detection capability, operating at 13.56 MHz with SPI slave interface, 256-byte FIFO buffer, and ultra-low-power Wait-for-Event (WFE) mode - deployed in consumer electronics such as laptops, printers, and smart TVs for secure item pairing and data exchange.

For engineers reviewing the RX95HF-VMD5T datasheet, RX95HF-VMD5T pinout, RX95HF-VMD5T application, or RX95HF-VMD5T equivalent, key selection considerations include its SPI-based host control architecture, ISO/IEC 14443-A compliance in tag emulation, field-detection wake-up capability, and VFQFPN32 5×5 mm package suitability for space-constrained NFC-enabled peripherals.

Technical Context

The RX95HF operates in two primary states: Active (Ready and Tag Emulation) and Wait-for-Event (WFE), with configurable low-power modes including Hibernate and Sleep/Field Detector. Wake-up is triggered exclusively by a ≥10 μs low pulse on IRQ_IN, and the LFO remains active in all low-power states to maintain timing integrity.

Its RF subsystem supports full ISO/IEC 14443 Type A tag emulation via an integrated AFE with dual receiver inputs (RX1/RX2), RF field detection logic, and programmable transmission/reception chains. Communication with the host MCU occurs exclusively over SPI - with polling or interrupt-driven operation - using a fixed 8-bit command protocol (e.g., PROTOCOLSELECT 0x02, LISTEN 0x05, IDLE 0x07) and register-level configuration of analog parameters via WRREG/RDREG commands.

Key Specifications

Pinout & Package

VFQFPN32 (5×5 mm, 0.5 mm pitch) with exposed thermal pad (shaded area in pinout diagram) requiring direct connection to GND for RF performance and thermal management.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PN7150 and ST25DV04K, RX95HF-VMD5T uniquely balances hardware-level ISO/IEC 14443-A tag emulation with host-controlled flexibility and field-sensing wake-up - making it optimal for embedded systems requiring deterministic, low-latency, MCU-managed NFC interactions without firmware stack overhead.

Availability

RX95HF-VMD5T is available at Aetrix Electronics and suitable for smart peripheral pairing, NFC-enabled printer setup, laptop secure login token, and set-top box content authorization requiring stable component supply across industrial and consumer OEM programs.

Supply support for RX95HF-VMD5T 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, specializing in microcontrollers, power management, sensors, and connectivity solutions for automotive, industrial, and consumer markets.

RX95HF belongs to ST's NFC transceiver product line, engineered specifically for host-controlled tag emulation in resource-constrained embedded systems - prioritizing RF reliability, ultra-low-power wake-up, and seamless SPI integration with MCUs.

FAQ

Does RX95HF-VMD5T support ISO/IEC 14443 Type B or FeliCa protocols?

No. The RX95HF-VMD5T supports ISO/IEC 14443 Type A tag emulation only, as confirmed in Section 1 (Description) and Table 9 of the datasheet. It lacks hardware blocks and firmware support for Type B, FeliCa, or NFC Forum Logical Link Control Protocol (LLCP). Its RF front-end and frame controller are optimized exclusively for Type A modulation and timing.

What is the minimum wake-up time from Hibernate mode?

The wake-up time from Hibernate mode is ≤100 μs, as specified in Figure 5 (Power-up sequence) and Section 3.1 (Operating modes). This includes t0 (initial wake-up delay, min 100 μs) and assumes IRQ_IN is asserted low for ≥10 μs. The LFO remains active during Hibernate, enabling rapid HFO restart and SPI interface reactivation.

Can RX95HF-VMD5T operate without an external crystal?

No. An external 13.56 MHz crystal connected between XIN and XOUT is mandatory. Section 6.6 (Oscillator characteristics) and Figure 2 (block diagram) confirm the absence of internal RC oscillator for RF carrier generation. Omitting the crystal prevents RF communication and causes failure during PROTOCOLSELECT command execution.

Is IRQ_OUT polarity active-high or active-low?

IRQ_OUT is active-low, as explicitly stated in Table 2 (Pin descriptions): "Pad internally connected to a Weak Pull-up to VPS" and Section 4.1.2 ("sets a low level on pin IRQ_OUT"). It remains low until the host reads the pending response via SPI, then returns high automatically - serving as a hardware handshake to replace polling.