$V_rm DD$-Hopping Accelerators for On-Chip Power Supply Circuit to Achieve Nanosecond-Order Transient Time

A V
_DD
-hopping accelerator for on-chip power supply circuits is proposed and the effectiveness of the accelerator circuit is experimentally verified. The quick dropper with the linear regulator enables nanosecond-order transient time in on-chip distributed power supply systems. The measured transition time is less than 5 ns with a load circuit equivalent to 25-k logic gates in 0.18-mum CMOS. This is to be compared with the case without the accelerator of the order of mus and thus the acceleration by two orders of magnitude is achieved. Extensions of the basic approach are also discussed including implementation of the quick dropper for a switching DC-DC converter, the control stability improvement, automatic timing generation, and the parasitic element effects of the power lines