Dual diode-Vth reduced power gating structure for better leakage reduction

Abstract

Leakage has become one of the most dominant factors of power management and signal integrity of nanometer scale integrated circuits. Recently, power gating structures has proven to be effective in controlling leakage. In this paper an alternative dual diode-Vth reduced power gating structure is proposed for better reduction of leakage currents, especially for low-power, high-performance portable devices. The proposed technique maintains an intermediate power saving state as well as the conventional power cut-off state. Experimental results have demonstrated that the proposed technique can significantly reduce leakage current and associated power consumptions during the HOLD and CUT-OFF power saving modes. It has also been demonstrated that the proposed technique significantly reduces ground bounce due to power mode transition.

Low Leakage Charge Recycling Technique for Power Minimization in Cntfet Circuits

“…Many power gating approaches [13][14][15][16] have been proposed for data retention with an intermediate power saving mode (drowsy mode) wherein a significant voltage difference is maintained across the circuit blocks by boosting the virtual ground voltage. Clamping devices like diodes and transistors are used for raising the virtual ground voltage.…”

“…This approach is not emphatically used to dynamically change the output voltage but instead only used to maintain an already calculated output voltage. Dual diode Vth approach [14] utilizes diodes in parallel with sleep transistors for the data retention. Sleep mode is lost in this technique and hence it is not suitable when the circuit remains idle for long periods.…”

“…Area overhead of dual switch and dual diode Vth approach is high because of additional diodes and transistors. In these techniques [13][14][15][16], the charge gets stored at the gate of the sleep transistor during active mode, and it is dumped to ground and wasted during mode transitions. No attempt is made to reuse the charge.…”