Stability Improvement Method For Ultra-Low-Power Bandgap Reference
In modern VLSI designs values of external voltage sources are not support high accuracy levels and currently schematic designs are implementing considering +/-10% variation of supply voltage values. However, such accuracy levels causing problems in sensitive analog parts where variation of reference voltages even with a few millivolts can result major inaccuracies. Such problems are meet in high speed data receivers where the swing of received data can be less than 100mV and it is required to detect the logic 0 or 1 levels transmitted from the sent from speed transmitter. Bandgap references are widely used as a solution of above-mentioned problems. While the inaccuracies and variations of modern semiconductor production technologies cause problems even in such a precision blocks as bandgap references. To evaluate the possible variations and design a consistent integrated circuits (IC) foundries are also providing their models. Designer are using these models in SPICE simulations and simulators support the Monte Carlo verifications to report the functionality of the blocks considering mathematical probability methods. In this paper the stability improvement method of bandgap references has been proposed where the nonstandard schematic solutions have been implemented to provide a precision reference voltage covering 4.5 sigma possible technology variation range.
analog, operational amplifier, integrated circuit, IC, VLSI, bandgap reference, reliability, Monte Carlo analysis, degradation