A low-power microcontroller having a 0.5 /spl mu/A standby current on-chip regulator with dual-reference scheme

We present a microcontroller having a 0.5 /spl mu/A standby current on-chip regulator. To save regulator area, we propose a dual-reference scheme in which one voltage reference circuit is provided for active mode and another voltage reference circuit is provided for standby mode. The dual-reference scheme reduces regulator area by 50% compared with a conventional scheme in which one voltage reference circuit is commonly used both in active mode and standby mode.