An Ultra-Low Leakage and Wide-Range Voltage Level Shifter for Low-Power Digital CMOS VLSIs

This brief presents an ultra-low leakage and fast conversion level shifter with wide-range voltage conversion and frequency. The proposed level shifter adopts the leakage shut-off transistors, which can completely cut off the static current when the circuits stand by. The pull-down network employs the low-threshold transistor for the fast fall transition. The proposed level shifter also solves the swing problem and achieves a fast conversion by using the voltage hysteresis transistor, strengthening the pull-up network to ensure the internal node is fast and fully charged. Measurement results based on the 55 nm process show that the average ultra-low leakage of the proposed level shifter is 34.8 pW when converting from 0.3 V input to 1.2 V output. Meanwhile, the average propagation delay and the average energy per transition of the proposed level shifter are 13.86 ns and 22.71 fJ for an input frequency of 1 MHz, respectively. The maximum conversion range is from 0.13 V to 1.2 V.