Author(s)

Yan Rongshen, Chan Chihang , Sin Saiweng, U Sengpan, Martins R. P.

Corresponding Author

Sin Saiweng

ABSTRACT

This paper presents a calibration scheme to enhance the robustness of the Self-Biased Ring Amplifier (SBRA) under PVT variations. As the ring amplifier is developed based on a ring oscillator structure, it can easily oscillate under PVT variations. The proposed calibration method utilizes an Oscillation Detection Circuit (ODC) with a close loop control of a Programmable Resistor Array Circuit (PRAC) to adjust the dead-zone (stability region), thus stabilizing the SBRA. The introduced ODC and PRAC have little influence on the power efficiency as well as hardware overhead. Based on a 1.5 bit/stage Multiplying Digital to Analog Converter (MDAC) circuit setup, the simulation shows that the proposed method can stabilize the ring amplifier in the range of 0°C to 85°C at all corners.

KEYWORDS

Calibration, Self-biased Ring Amplifier, PVT Variations, Oscillation Detection, Programmable Resistor.