BurdenVoltage

BurdenVoltage is a term used in current sensing to denote the voltage developed across the burden element that the sensing device drives. In this context, the burden is the resistor or load connected to the sensing element, such as the shunt resistor in a low-side or high-side current sensor or the burden resistor in a current transformer or Hall-effect sensor. The burden voltage is therefore the product of the sensed current and the burden resistance, V = I × R_burden. The magnitude and stability of this voltage directly affect measurement accuracy, linearity, bandwidth, and noise performance.

Design and operational considerations: The burden voltage must lie within the sensor’s specified range. If it is too large, the sensor saturates, loses linearity, or overheats; if too small, the signal may be dominated by noise and quantization errors. Thermal drift of the burden resistor further affects accuracy. Proper layout and compensation are important.

Practical guidelines: Choose a burden resistor that provides adequate voltage swing for the ADC or subsequent circuitry while staying within the sensor’s maximum burden rating. Use precision resistors with low temperature coefficient. In high-speed or high-current applications, consider parasitics such as inductance and capacitance, and ensure the voltage sense path is shielded and decoupled.

Applications: BurdenVoltage concepts are used in power supplies, motor drives, battery management systems, energy metering, and instrumentation amplifiers.

See also: Shunt resistor, Hall effect sensor, current transformer, current sense amplifier.