A 1.2V Core Switched Geometry Schmitt Trigger Relaxation Oscillator

Relaxation oscillators can provide a large frequency range whilst maintaining low power consumption and reduced area. The main drawback of most of the Schmitt trigger-based oscillators is the supply voltage switching point variation, which has a profound influence on the output frequency spread. The present work analyses a low voltage core, switched geometry Schmitt trigger relaxation oscillator, with local, low voltage supply, provided by a low dropout internal regulator. The power consumption of the schematic is optimized by using the low voltage core, while the local regulator accommodated the schematic functionality for the supply voltage range between 1.6 and 5.5V.