Differential Oscilloscope Probes

Differential oscilloscope probes measure voltage between two points without referencing either to ground. This makes them the correct choice for floating circuits, motor drives, switch-mode power supplies, and signals where a single-ended probe would create a ground loop or damage the circuit. Key selection criteria are bandwidth, attenuation ratio, and maximum input voltage. Bandwidth spans 20 kHz for low-frequency power work to 2 GHz for high-speed digital signals. Attenuation ratios of 1:100 and 1:1000 determine how far the probe scales down the signal before it reaches the oscilloscope input.

Active differential probes draw power from the oscilloscope or an external supply and deliver flat frequency response across their rated bandwidth. Passive types suit lower frequencies and cost less, but check the maximum common-mode voltage rating before connecting to high-voltage rails. Connector types include BNC and banana, so confirm compatibility with your oscilloscope input before ordering.