Reference Precision
Voltage references provide a constant potential by utilizing the difference in energy levels within a semiconductor. This bandgap voltage reference stability quantifies the deviation of the output voltage from its nominal value over specified operating conditions and periods. Measurement of the parameter determines the reliability of analog to digital conversions in precision instrumentation.
Thermal Variation
Temperature changes represent the primary cause of output fluctuation in these circuits. The bandgap voltage reference stability is maintained by compensating for the positive temperature coefficient of a base-emitter voltage with the negative coefficient of a thermal voltage. Compensation accuracy depends on the matching of transistor pairs and the precision of the resistor network.
Temporal Aging
Long term drift occurs as the physical properties of the silicon and the package stress change over months of operation. This bandgap voltage reference stability is verified through accelerated life testing at elevated temperatures to predict the performance over the service life of the device. Stress relief through careful die mounting and package selection helps maintain the output within millivolt tolerances.
Voltage Noise
Random fluctuations create uncertainty. High frequency components are removed by capacitors to improve the bandgap voltage reference stability. Filtering is required.
