| Specification |
Definition |
Key Applications / Use Cases |
| Output Voltage (VREF) |
The nominal voltage the reference is designed to provide (e.g., 1.25V, 2.5V, 4.096V, 5V). |
Sets reference level for ADCs, DACs, regulators, and comparators |
| Initial Accuracy |
Deviation of the output voltage from its nominal value at room temperature (typically in % or mV). |
Precision measurement, calibration-free systems |
| Temperature Coefficient (Tempco) |
Change in output voltage per degree Celsius, expressed in ppm/°C. |
Temperature-sensitive systems, high-precision instrumentation |
| Long-Term Stability / Drift |
Change in output voltage over time, typically over 1000 hours or more. |
Metrology, industrial monitoring, long-lifetime systems |
| Load Regulation |
Change in output voltage as output current changes (e.g., mV/mA). |
Systems with variable load like ADC/DAC or sensor excitation |
| Line Regulation |
Change in output voltage due to changes in supply voltage (e.g., μV/V or ppm/V). |
Power supply rejection, battery-powered or noisy environments |
| Output Noise |
RMS noise within a specified bandwidth (e.g., 0.1 Hz–10 Hz, or 10 Hz–1 kHz). |
Low-noise ADCs, audio, test equipment, high-resolution systems |
| Output Current Capability |
Maximum output current the reference can source or sink without violating regulation specs. |
Driving ADC/DAC loads, biasing circuits, analog peripherals |
| Quiescent Current (IQ) |
Current consumed by the reference with no load; key in low-power designs. |
Battery-powered devices, wireless sensors, handheld instruments |
| Startup Time |
Time required for the output to reach its final value after power-on. |
Time-critical systems, pulsed-mode power domains |
| Output Impedance |
The small-signal resistance seen at the reference output; lower is better for load regulation. |
Driving dynamic or capacitive loads, bufferless ADC/DAC interfaces |
| PSRR (Power Supply Rejection Ratio) |
Ability to reject changes in supply voltage; often specified in dB. |
Suppressing ripple from switching regulators, automotive or industrial power |
| Temperature Hysteresis |
The output voltage shift after the device is cycled through a temperature range. |
Systems requiring frequent recalibration or exposed to temperature swings |
| Shunt vs. Series Topology |
Shunt references act like Zener diodes; series references act like regulators. |
Series: general low-noise precision. Shunt: voltage clamping, external drive |
