Robust Design of Differential Amplifier with Diode-connected Voltage Reference

摘要

Objectives: The impact of process, voltage and temperature (PVT) variations on the voltage gain of a CMOS differential amplifier is investigated. Methods and analysis: Appropriate biasing is provided using diode-connected MOS voltage dividers. These dividers are less bulky as compared to their resistive counterparts, save chip area and provide better performance when subjected to variations. In addition, the transistors are sized suitably to minimize the effect of threshold voltage modulation in short-channel devices. Findings: The sensitivity parameters for the voltage gain are modeled and their dependences are studied. All simulation results have been performed using Virtuoso Analog Design Environment of Cadence @ 45-nm technology node. Application/ Improvement: Diode-connected MOS voltage dividers are used to bias the amplifier which provide immunity against PVT variations and hence improve system performance.