Oscilloscope Probes
Oscilloscope Probes
Oscilloscope probes are the critical interface between a circuit under test and an oscilloscope input. Probe selection directly affects measurement accuracy, bandwidth, loading effects on the circuit, and measurement safety. Passive probes are the most common type, providing reliable performance up to several hundred megahertz. For high-frequency or differential measurements, active probes, differential probes, and current probes offer specialized capabilities with higher bandwidth and minimal circuit loading.
High-performance probes from Keysight's InfiniiMax series and Tektronix support bandwidths from 1 GHz to over 30 GHz, making them essential for signal integrity work on high-speed digital interfaces, SerDes links, and RF circuits. Proper probe selection — considering bandwidth, input capacitance, probe tip geometry, and safety category — is fundamental to obtaining accurate oscilloscope measurements. Probe accessories such as browser tips, solder-in tips, and ground lead adapters further expand measurement flexibility in lab and field environments.
Typical Applications
- High-speed digital signal integrity: measuring eye diagrams and edge rates on PCIe, DDR, and HDMI interfaces
- Differential measurements: isolating floating signals in power electronics and motor drives
- Current measurement: capturing current waveforms using clamp-style current probes for power analysis
- RF and microwave: probing RF signals up to millimeter-wave frequencies with active probes
- Automotive electronics: measuring CAN, LIN, and high-voltage hybrid vehicle signals with isolated probes
- EMC pre-compliance testing: capturing near-field emissions and power-line disturbances
Popular Brands
Keysight's InfiniiMax probe system offers modular probe amplifiers supporting bandwidths up to 30 GHz with interchangeable browser and solder-in tips. Tektronix provides an extensive probe portfolio including passive, active, differential, current, and high-voltage probes. Rohde & Schwarz, Teledyne LeCroy, and PMK also offer specialized probes for demanding measurement applications.
