Referenssijännitelähde

A referenssijännitelähde, or voltage reference, is an electronic component that produces a stable and accurate voltage output, regardless of variations in input voltage, temperature, or load. This stable output voltage serves as a reliable reference point for other electronic circuits.

These devices are crucial in applications where precise voltage levels are required for accurate measurements or control. Examples include analog-to-digital converters (ADCs), digital-to-analog converters (DACs), voltage regulators, and measurement instruments. The accuracy and stability of a voltage reference directly impact the performance of the entire system.

Referenssijännitelähteitä can be broadly categorized into shunt and series types. Shunt references are typically simpler and draw current from the power supply only when needed, making them suitable for low-power applications. Series references, on the other hand, are more complex but offer better performance in terms of noise and load regulation, often used in precision instrumentation.

Key parameters for evaluating a voltage reference include its initial accuracy, temperature coefficient (how much the output voltage changes with temperature), long-term stability, and output noise. Different technologies are used to realize voltage references, such as Zener diodes, bandgap references, and buried Zener diodes, each offering a trade-off between performance, cost, and power consumption. The choice of a voltage reference depends heavily on the specific requirements of the application.