KEY FEATURES:
Works with all power rail probes
Small form factor fits easily into your test setup
No adjustments necessary
One male and one female SMA connector, making it easy to insert into your test setup.
Maintains 50 Ohm transmission line integrity and signal bandwidth to > 2GHz
Works with all types of test equipment to eliminate ground loops, such as Network Analyzers, Oscilloscopes and Spectrum Analyzers
 
BENEFITS:
Greatly attenuates errors associated with the ground loop in oscilloscope measurements
Improves the accuracy of power rail probes
Reduces cable shield induced ground loop errors regardless of the test setup
Easy to add multiple J2115A for as many channels as are needed in a test setup
 
WHAT'S INCLUDED:
QTYx2 J2115A Coaxial Isolators
One (1) Year Manufacturer’s Warranty
 
DESCRIPTION:
The Picotest coaxial isolator is a common mode transformer that minimizes the ground loop in power rail and other forms of voltage probe measurements that exists in all oscilloscope, and other instrument setups.
 
It may come as a surprise to some of you, but there is a ground loop created due to the front panel of your instrument and the cable connections at the DUT. This front panel ground appears across the various scope input channels. Offsets in this ground voltage at the DUT translate to voltage inaccuracies in your oscilloscope measurements. The common mode ground signal at the DUT is additive
with the desired test signal, and it needs to be diminished and/or effectively eliminated. It can result in mV to tens, or even hundreds of mV of measurement offset.
 
There is a simple fix to the impacts of the ground loop and it’s the J2115A coaxial isolator. The J2115A is necessary to achieve the most accuracy out of your oscilloscope measurements, in particular power rail probe measurements, but also other voltage probe measurements.
 
Ground loop errors mostly impact sensitive circuits, such as PLLs or LNAs, but also create VDD droop and ground bounce errors in high power ASIC cores. These ground loops occur when 2 or more cable shields are connected to “ground” at both ends, with voltage differences between the ground shields at the DUT. There are several papers on the subject shown below, but there are a few ways to manage the ground loops:
 
Reduce the ground connection impedance using low shield resistance cable such as PDN cable
Make at least the most sensitive channel connection as short as possible
Add common mode isolators. This is the most effective solution.
 
 
Error Note: The ground error is fixed and has nothing to do with the signal amplitude. Representing it as a % isn’t really accurate, but it could easily be hundreds or even thousands of %. The measurement is equal to the ground error plus the signal. These are independent. With no signal, you’ll still see the ground error, indicating an infinite % error.
 
NOTE: Price shown is per J2115A pair.