A 13.56 MHz Radio Frequency Identification Transponder Analog Front End Using a Dynamically Enabled Digital Phase Locked Loop

Abstract

The analog front end (AFE) of a radio frequency identification transponder using the ISO 14443 type A standard with a 100% amplitude shift keying (ASK) modulation is proposed in this paper and verified by circuit simulations and measurements. This AFE circuit, using a 13.56 MHz carrier frequency, consists of a rectifier, a modulator, a demodulator, a regulator, a power on reset, and a dynamically enabled digital phase locked loop (DPLL). The DPLL, with a charge pump enable circuit, was used to recover the clock of a 100% modulated ASK signal during the pause period. A high voltage lateral double diffused metal-oxide semiconductor transistor was used to protect the rectifier and the clock recovery circuit from high voltages. The proposed AFE was fabricated using the 0.18 µm standard CMOS process, with an AFE core size of 350 µm × 230 µm. The measurement results show that the DPLL, using a demodulator output signal, generates a constant 1.695 MHz clock during the pause period of the 100% ASK signal.

Evaluation of Contactless Identification Card Immunity against a Current Pulse in an Adjacent Conductor

“…This design uses NMOS and PMOS transistors as a controlled load directly connected to the antenna terminals to limit the RF power in the chip. The analogue front-end for the 13.56 MHz transponder, including a powering circuit based on lateral MOS transistors, is described in [21,22]. The influence of a parallelconnected energy harvester on RFID transponder performance is modelled and measured Therefore, this article aims to measure Mifare chip characteristics and conduct a mathematical and simulation analysis of the induction of possibly dangerous current pulses in identification card circuits.…”

“…This design uses NMOS and PMOS transistors as a controlled load directly connected to the antenna terminals to limit the RF power in the chip. The analogue front-end for the 13.56 MHz transponder, including a powering circuit based on lateral MOS transistors, is described in [21,22]. The influence of a parallel-connected energy harvester on RFID transponder performance is modelled and measured in [23].…”

Modelling and Design of HF RFID Passive Transponders with Additional Energy Harvester

“…The synthesis of rectifier and voltage regulator is made separately [39,40]. Although the rectification takes place in a half-wave or full-wave rectifier [41], it is controlled by the voltage regulator [39].…”

“…The synthesis of rectifier and voltage regulator is made separately [39,40]. Although the rectification takes place in a half-wave or full-wave rectifier [41], it is controlled by the voltage regulator [39]. In the case of passive transponders working in the HF band, both of the circuits are commonly realized on fast switching diodes in MOS technology [42].…”