As modern battery powered devices and integrated
circuits become more green and energy efficient there is a growing need to make high sensitivity
low level current measurements to ensure that the current consumption of these devices is within acceptable limits.
The new N2820A Series high sensitivity current probes from Keysight
Technologies address the need for high sensitivity current measurements with a wide dynamic range.
These probes also offer the advantage of physically small connections to the device under test
since today's application environments require an extremely small form factor.
Many engineers prefer to use an oscilloscope to measure current consumptions of a device with respect to time.
One way to measure a current with an oscilloscope is to use a
clamp-on type current probe to directly monitor the current going into the device.
Unfortunately, this approach is not appropriate for measuring small currents that rapidly change between sub-milliamps and several amps.
A result is this example showing the current consumption
of a mobile phone where the dynamic behavior of the phone's low level current is not measurable.
Also to acquire a more accurate measurement, an engineer would have to routinely degouse
the probe to remove residual magnetism from the probe core and to help compensate for any D.C. offset.
This extra calibration procedure makes the clamp-on current probe cumbersome to use.
Now, let's try the same measurement with Keysight's
N2820A two-channel high sensitivity current probe.
This probe comes with two parallel differential amplifiers with different gain settings.
The low gain side allows you to
see the entire wayform or the zoom out view of the wayform.
And the high gain amplifier provides a zoom-in view for observing extremely small current fluctuations such as a mobile
phone's idle state current.
Simply connect the probe's primary channel to one oscilloscope
input channel and the probe's secondary channel cable to another channel.
With Keysight's Infinium oscilloscopes, the N2820A provides for simultaneous high and low gain views of
the current wayform. This results in a more precise wide dynamic range measurement.
The connection to a device under test is made by using the make-before-break or MBB interface
that comes with the N2820A probe.
The MBB header is connected to the sensor head on the probe and mounted on the DUT board.
The MBB's are a great way to connect and disconnect across multiple locations on the target PCB without interrupting the device.
With current wayforms captured, you now want to calculate the average current consumption
of the system over time.
Keysight's Infinium scope provides an area under a curve measurement
where you can easily calculate the integrated current consumptions over time.
Engineers rely on accurate current measurements but a scope's inherent noise is often a key contributor
to measurement inaccuracy when viewing small signals.
Keysight's N2820A Series probes, together
with Keysight's new Infinium 9000 H-Series oscilloscope, delivers the ultimate high-definition measurement solution.
The 9000 H-Series has a 12-bit vertical resolution and reduces noise by 3 times compared
to the noise inherent in traditional 8-bit oscilloscopes.
This enables precision signal viewing even for small signals.
Find out more about Keysight's revolutionary
N2820A Series high sensitivity current probes by visiting www.keysight.com/find/N2820A.