Tag IC

Tag IC

The RFID tag integrated circuit." data-category="General">Tag IC (Integrated Circuit) is the silicon chip at the heart of every RFID transponder. It contains the RF analogue front-end, digital logic, and non-volatile memory that enable the tag to harvest energy, process reader commands, store data, and modulate the backscatter response.

Internal Architecture

A modern UHF RFID Tag IC integrates several functional blocks on a single die:

• RF front-end -- rectifier, voltage regulator, clock recovery, and modulator/demodulator.
• Digital controller -- state machine implementing the EPC Gen2 protocol, including anti-collision, singulation, and command processing.
• Memory -- four banks: Reserved (passwords), EPC Memory (Bank 1), TID Memory (Bank 2), and optional User Memory (Bank 3). Memory is EEPROM with write endurance of ~100,000 cycles and data retention of 20+ years.
• Security engine (advanced ICs) -- AES-128 or other crypto suite implementations for mutual authentication and tag authentication.

Key Manufacturers and Chips

Die Size and Cost

Die size directly determines tag IC cost. A smaller die yields more chips per silicon wafer, reducing unit cost. Current high-volume UHF tag ICs have die areas of 0.1-0.4 mm squared. The industry drives relentlessly toward smaller process nodes (currently 55-65 nm) to lower the per-tag cost floor. At scale, the IC contributes $0.01-$0.03 to total tag cost.

Selection Criteria

Engineers choose a Tag IC based on: sensitivity (determines read range ceiling), memory capacity (EPC-only vs. extended user memory), security features (crypto suite support), power consumption profile, and supported protocol features (Gen2v2, untraceable command, protected mode).

See also: Inlay | EPC Memory | Tags