Design and analysis of very low voltage charge pumps for RFID tags

The design and analysis of very low-voltage driven charge pumps powered by RF telemetry is proposed. The use of thick oxide zero threshold voltage transistors along with appropriately sized boosting capacitors and matching techniques allows for charge pumps capable of achieving high voltage DC outputs with very low input voltages. Two test chips have been fabricated, an 11 stage pump and a 12 stage pump in 1.2 V 0.13-mum standard CMOS process. The pumps are capable of generating an output voltage above 1.2 volts with input voltages below 100 mV making them ideal for generating DC supplies from low RF scavenged sources.