AS3911B-AQFM STMicroelectronics Integrated Circuit (Quad Flat No-Lead) In Stock
The AS3911B-AQFM is a high-performance NFC/HF RFID reader IC from STMicroelectronics operating at 13.56 MHz. It supports ISO 14443 A/B and ISO 15693 protocols with an integrated transmitter, receiver, and SPI interface, housed in a compact 32-pin 5x5 mm QFN package.
- Manufacturer
- STMicroelectronics
- Package
- Quad Flat No-Lead
- Pin Count
- 33
- Lifecycle
- ACTIVE
- Datasheet
- AS3911B-AQFM Datasheet PDF
- Category
- Integrated Circuit
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- Supports multiple NFC and HF RFID standards including ISO 14443 A/B and ISO 15693 at 13.56 MHz
- Integrated transmitter with programmable output power up to 500 mW for flexible antenna drive
- SPI interface up to 10 MHz enables fast communication with host microcontrollers
- On-chip automatic collision avoidance and wake-up timer reduce host processor load
- Compact 32-pin 5x5 mm QFN package simplifies PCB integration in space-constrained NFC readers
Applications
The AS3911B-AQFM is designed for contactless payment terminals, access control readers, and industrial RFID gate systems that require multi-standard 13.56 MHz NFC/RFID capability. It is widely used in smart metering, healthcare wristband readers, and retail point-of-sale devices where reliable ISO 14443 and ISO 15693 card reading is essential. The device also enables IoT proximity detection and asset tracking applications leveraging its low-power wake-up and autonomous collision-avoidance features.
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
Alternate & Equivalent Parts
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
Which NFC and RFID protocols does AS3911B-AQFM support at the 13.56 MHz carrier frequency?
The AS3911B-AQFM supports ISO 14443 Type A and Type B (used in most credit cards and passports) as well as ISO 15693 (used in vicinity RFID tags) at the standard 13.56 MHz HF carrier frequency. This multi-protocol support allows a single reader design to handle diverse contactless card and tag ecosystems without hardware changes.
How does the integrated transmitter output power of AS3911B-AQFM affect antenna and range design?
The AS3911B-AQFM includes a programmable transmitter capable of up to 500 mW output power to the antenna, enabling designers to tune the effective read range from a few centimeters up to the ISO 14443 standard 10 cm or ISO 15693 up to 70 cm. Higher output power settings extend range but require appropriate antenna matching and EMI filtering to meet regulatory limits.
What host interface does AS3911B-AQFM use and at what speed can data be transferred?
The AS3911B-AQFM communicates with a host microcontroller via an SPI interface running at up to 10 MHz, providing fast register access and FIFO data transfers. This high-speed SPI port ensures that the host can read card data, configure the receiver parameters, and manage interrupt events with minimal latency in real-time contactless applications.
In which package is AS3911B-AQFM available and how does it help with board density in portable NFC devices?
The AS3911B-AQFM is housed in a 32-pin QFN package measuring 5 mm x 5 mm with an exposed thermal pad for heat dissipation. This compact form factor allows the NFC reader IC to fit on small PCBs typical of handheld terminals, wearable payment devices, and embedded IoT modules where mounting area is limited to a few square centimeters.
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About STMicroelectronics
STMicroelectronics is a global semiconductor leader serving customers across the spectrum of electronics applications. ST's products are found in a wide range of applications including automotive, industrial, personal electronics, and communications.
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