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The proposed UHF Gen2 RFID chip expands its applications to both FFC and NFC through dual field communication scheme with the dual antenna ports. An RF front end circuit with dual field communication antenna ports and the embedded FeRAM technology on the passive UHF Gen2 RFID chip enables the excellent operating performances and the low cost chip for the tag chip applications from the item level to pallet. The metal-ferroelectric-metal (MFM) capacitor, which is the replacement capacitor device for metal-insulator-metal (MIM) or poly-insulator-poly (PIP), is composed of the ferroelectric material as a dielectric insulator. The MFM capacitor is made simultaneously during the FeRAM memory cell process integration without any additional process integration cost. The MFM capacitor of PZT with the thickness of 0.15μm has the high capacitance value of 20–40 fF at unit μm2 area size. The MFM can be stacked over the CMOS layout area, which saves dramatically the capacitor layout area. The MFM capacitor also has th...

The maximum peak-to-peak radio frequency (RF) signal antenna voltage level can be extended to reach to over 12 Vpp, −6 V to +6 V. Thus it is desirable that the electro-static discharge (ESD) device does not turn on at the normal operating RF antenna signal voltage level. The turn-on threshold negative voltage of the ESD device of the PN diode type is around −0.5 V in the conventional radio frequency identification (RFID) chip. The asymmetric threshold voltage characteristics of the ESD device of the RFID chip makes the distortion of the RF antenna signal at the high intensity RF input field. In the proposed floating base vertical PNP ESD device, N-type doped N-WELL floating base is sandwiched between two p-type P+ emitter and P-WELL collector. Floating base BJT ESD device enhances the performance of parasitic BJT current in the ESD mode. During the negative voltage phase of RF antenna input signal, the negative voltage of RF antenna input is extended to around −10 V. This extension of RF antenna ...

N-WELL floating base is sandwiched between P+ emitter and P-WELL collector in the proposed floating base vertical PNP electro-static discharge (ESD) protection device. Floating base bipolar junction transistor (BJT) ESD protection device increases the current performance of the parasitic BJT in the ESD mode. During the negative voltage phase of RF antenna signal, the negative voltage range of RF antenna signal is extended to around −10 V at the high RF power field without latch-up failure. The minimum P+ anode layout area of the floating base type BJT ESD device is 400 μm2 for the target ESD voltage of 2000 V in human body model (HBM) mode. The parasitic capacitance of the floating base type BJT ESD protection device is about 0.4 pF. The layout area of the proposed floating base type BJT ESD protection device is 50% smaller that of the conventional NMOS diode type ESD protection device for the target ESD voltage of 2000 V in HBM mode. The rewards of the floating base type BJT ESD device will come...

The metal-ferroelectric-metal (MFM) capacitor in ferroelectric random access memory (FeRAM) security embedded RFID chip is used not only in the memory cell region but also used in the analog and digital circuit area for low cost capacitance device and high security algorithm. MFM based security FeRAM braces for a wide range of security threats such as reverse engineering, cloning, and tampering. High security performance solution of on-chip FeRAM based register key is implemented to prepare against security attacking. RF transferring sensitivity properties with MFM capacitor are almost same or better than that with poly-insulator-poly (PIP) capacitor and metal-insulator-metal (MIM), and MOS capacitor. The measured power consumption of FeRAM embedded RFID chip without crypto processor engine is about 10μ W with the write sensitivity of -18dBm.

For a longer working distance between passive tags and the reader, the ferroelectric based technologies are proposed in UHF (860–960 MHz) band transponder. The small ferroelectric capacitor layout area with a stacked capacitor structure over circuit region and a large dielectric permittivity of 250 to 500 and small 1T1C cell array layout area with simple 2T2C based reference scheme allow small chip size. The low operation voltage of 1.5 V to 2.0 V without high voltage boosting scheme also contribute to small power consumption and low cost.

In this paper, we propose a phase-locked loop (PLL) with dual PFDs in which the advantages of both PFDs can be combined. The sequential PFD has an unlimited error detection range and the precharge PFD has one and a half times better resolution performance than the sequential PFD. Therefore, by operating the appropriate PFD connected to the well-adjusted charge pump and regulating the ratio of loop bandwidth to input frequency during the acquisition process, an unlimited error detection range, a high frequency operation, a reduced dead zone and a higher speed lock-up time can be achieved. This structure can improve the trade-off between acquisition behaviour and locked behaviour. The proposed PLL structure is designed to use 1.5 μm CMOS technology with 5 V supply voltage.