RFID issue

dick_freebird said:

Inductors (real ones) have a shunt C just like capacitors have shunt L. Go high enough in freq and you may see that "turn up", presuming it's modeled.

Anything you hang on the circuit pays some kind of tax.

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I am designing LF passive RFID transponder chip for animal tagging applications (ISO 11784/11785) . The operating frequency is 134.2K hz . Basically the reader has 50 Ohm impedance and due to inductive coupling , the chip is powered on. For this purpose , I have to match the input impedance of chip ie 50 Ohms , this will produce 300mV at input of chip at 10cm distance (10dB power). My matching network should be as such to have an input impedance of 50 Ohm . So i am stuck at RF-DC part of this chip. It includes the matching network followed on by a dickson multiplier. The dickson multiplier gets , lets say , 300mV at input , and after 6-7 stages , it multiplies and provides 1V at output . But as soon as i connect some load (an LDO) to it , the voltages drop down , I dont have enought current at output of Dickson multiplier. Why is it happening ?
I am using TsmcN65 nm technology

I don't think there's a significance of 50 ohm impedance matching for LF RFID design. Receiver input should be high impedance, coil can be designed for optimal power supply. I would refer to design of commercial RFID chips for this standard in the first place.