Picotest P2104A 1-Port-Übertragungsleitungs-PDN-Sonde

The Picotest P2104A is a referred to as a 'browser' Probe for its ability to easily and quickly be moved from point-to-point/rail-to-rail simply by reseating the probe points. The probe achieves a very low inductance at the tip to mitigate space constraints on a dense PCB, while eliminating the need to add additional SMA connections or other test points necessary for impedance measurements. It is especially useful when there are multiple rails to assess and there is not time or PCB iterations available to provide test point implementations for each. Repeated measurements are simplified because connection is by simply touching the tip to existing output capacitor pads. The P2104A comes in one of four fixed pin pitches (50, 60, 70, or 100 mil spacing). The pin pitch is fixed and not interchangeable. The P2104A probe tips are available as 1X, 2X, 5X, or 10X attenuations. An AC coupled option providing DC blocking is also available along with the 1X attenuation option. This allows flexibility for users to measure across a wide range of voltages and capacitor sizes. As an example, the upside of the 2X attenuation probe is that it can measure 6.5VDC without DC blocks. The tradeoff is the attenuation increases the impedance floor. In short, this 1-port P2104A probe is best suited for VRM, power plane, and decoupling measurements. An added benefit is that you can use Non-Invasive Stability Measurement (NISM) to assess power supply's stability at the same time as you assess the PDN impedance.

The probe is compatible with all 50 ohm instruments, including vector network analyzers (VNAs), oscilloscopes, and spectrum analyzers.

The probe is designed to work with the traditional 1-port reflection impedance setup. A source power amplifier such as the OMICRON Lab B-AMP 12 (OL000168) can help measure ultra-low impedance magnitudes.

What's a Transmission Line Probe

Transmission line probes are a special type of passive probe that replaces the high impedance probe cable found in a traditional passive probe with a precision transmission line that has a characteristic impedance that matches the oscilloscope's input (50 ohms). This greatly reduces the input capacitance to a fraction of a picofarad, minimizing the loading of high frequency signals. The probes are referred to as 'PDN' probes, because of their effective use in measuring the low and ultra-low impedances found in power distribution networks.

The input impedance of the Picotest probes remains nearly constant over their entire frequency range. A traditional ÷10 passive probe has a high input impedance at DC; however, this impedance drops rapidly with frequency, passing below the input impedance of a transmission line probe at <100MHz. The probes are useful in applications that produce fast rising, narrow pulses with amplitudes which exceed the dynamic range of active probes. They also tend to have less parasitic effects on frequency response, so they are ideal for measuring impedance. By providing a simple yet elegant solution to probing high-frequency signals, Picotest's one and two-port transmission line probes preserve signal fidelity and allow high-bandwidth test equipment to properly measure circuit characteristics.