highsidelowside

Highsidelowside is an informal term used in electrical engineering to refer to the set of configurations that place switching elements, current-sense elements, or measurement circuits either on the high (supply) side or on the low (return) side of a load. In practice, discussions of highsidelowside contrast high-side and low-side arrangements in power electronics, motor control, and instrumentation.

High-side configurations place the control element and/or the current-sense element between the supply and the load. This arrangement keeps the load reference near the supply voltage and allows measurement of load current with respect to the supply rail. High-side switching is common in automotive and battery-powered systems because it can provide protective advantages for the load and enable fault detection close to the source.

Low-side configurations locate the switch or the sense resistor between the load and ground. This simplifies driving the switch, particularly with N-channel devices, and makes current sensing straightforward because the sense voltage is referenced to ground. Low-side designs are typically cheaper and easier to implement but can offer less protection in certain fault conditions and may complicate grounding in mixed-signal systems.

Modern designs often use both approaches as required, and many circuits employ dedicated high-side current-sense amplifiers or isolated drivers to manage large common-mode voltages. The choice between high-side and low-side hinges on factors such as voltage levels, isolation needs, measurement accuracy, and cost.