IsoVu™ Isolated Current Probes

Overview

TICP Series IsoVu™ isolated current probes deliver exceptional bandwidth, noise rejection, accuracy, and ease of use for making current measurements.

Complete galvanic isolation eliminates ground loops and enables very high common mode rejection. In a 1X configuration, the TICP Series probe's 50 Ω input offers extremely low noise of less than 4.7 nV/√Hz, ideal for making accurate measurements on shunts. The probes offer a variety of attenuation tips to extend the differential voltage range. Depending upon the shunt used, the probes can perform current measurements from microamperes (µA) for low-power mobile designs to hundreds of amperes for industrial and mobility systems.

Key performance specifications and features

• Galvanic isolation between probe tip and the oscilloscope
• Available in three bandwidths: 1 GHz, 500 MHz, and 250 MHz
• Wide current measurement range determined by the shunt used with 1X, 10X or 100X probe tips
• Noise <4.70 nV / √Hz (<21 μV_RMS at 20 MHz)
• Up to 90 dB CMRR at 1 MHz
• Maximum common mode voltage: 1.8 kV; For use in a Pollution Degree 1 environment; transient level not to exceed 5 kV_pk
• 1.5% DC gain accuracy
• Compatible with the 4, 5, and 6 Series MSO instruments, including the latest B models
• TekVPI™ interface enables control and probe configuration from the oscilloscope front panel or programming interface

Key applications

• Current shunt measurements
• Half/full bridge designs using SiC or GaN, FETs, or IGBTs
• Double pulse testing (DPT)
• Floating gate measurements
• Power converter designs
• Switching power supply designs
• Steady state, sleep, and wake-up state current monitoring

Tips expand measurement ranges, minimize hassle, and reduce noise

TICP Series probes are well-suited for both low current and high current measurements that are challenging or impossible with sensor-based clamp-on oscilloscope probes. With three different attenuation tips, you can easily measure a wide range of currents based on the shunt resistance and its power rating.

The probes are designed to provide high-performance current measurements while offering convenient connectivity. Tips are equipped with MMCX and SMA connectors to ensure proper grounding and shielding, which is crucial for minimizing noise, ground loops, and ensuring accurate current measurements. These tips enable direct connection to most commercially available shunts, but you can also use appropriate adapters to interface the tips with their shunts.

The probe tips connect to the probe body with a unique reversible IsoConnect™ interface, allowing you to snap-fit the tips without worrying about orientation. Designed for flexibility, the probe tips have a small bend radius, facilitating connection in tight spaces. The standard probe includes a tripod adapter and a bipod for convenient placement and positioning in the test setup.

Current shunt measurements

There are two methods to measure current in test systems. The first method involves sensing the fields around the electrical conductors and converting them into signals that represent the current. This method is used by most clamp-on style current probes, or Rogowski coils. The second method involves measuring currents using Ohm’s law. One can measure current by measuring the voltage drop across a precision shunt resistor, which is the method used by the TICP Series probes.

Current shunts, or current viewing resistors (CVRs), typically have a wide frequency response, accurately measuring both AC and DC currents across a broad spectrum of frequencies. Their compact size allows for easy integration into existing circuitry with minimal space requirements. Although shunt resistors must be designed into a PCB and result in voltage drop, they offer some key advantages compared to sensor-based current measurements, including high accuracy, minimal distortion, and low interference.

Isolation enables floating measurements and exceptionally low noise

TICP Series IsoVu isolated current probes enable you to make more accurate dynamic current measurements on your oscilloscope, outside traditional limits.

Unlike transformer, Rogowski, or Hall effect current probes, TICP current probes enable measurements from DC to hundreds of MHz when paired with high-performance shunts or CVRs. Complete RF isolation between the probe tip and the oscilloscope eliminates ground loops and helps deliver extraordinary common mode rejection (CMRR) up to 90 dB at 1 MHz to dramatically reduce common mode noise. Low attenuation and low input impedance (50 Ω) limits noise contribution to less than 4.7 nV/√Hz noise contribution (<150 µV at 1 GHz) when measuring low voltages (± 0.5 V) across shunts.

Measuring high-fidelity currents in high power systems

TICP Series probes provide the bandwidth you need to accurately see the fast risetimes of wide bandgap (WBG) switching devices. This enables you to accurately measure dynamic currents in high-power SiC and GaN power converters. They complement the groundbreaking IsoVu™ TIVP isolated voltage probes and represent a similar isolation breakthrough for current measurements. The isolation eliminates ground loops and enables accurate measurements of high-side drain currents (Ids).

Measuring low currents in low power systems

TICP Series probes have the bandwidth to measure current consumption during specific system activities and transitions from sleep to active states. The low-noise architecture is critical for accurately measuring low currents across the shunts. The common mode voltage rating of TICP Series is higher than most differential probes, enabling current shunt measurements on higher voltage power rails. When paired with the low-noise of the 6 Series MSO, the overall system offers low-noise performance to efficiently measure rail currents.