03 | Keysight | CX3300 Series Device Current Waveform Analyzer - Data Sheet
Greater demand for transient current measurements
Researchers working on advanced semiconductor or non-volatile memory devices
such as ReRAM and PRAM are struggling to observe the behavior of newly developed
materials when a short voltage pulse (< 100 ns) is applied. Since the transient current
ranges from sub-nA to over mA, it is very difficult to clearly detect entire transient
current behavior.
Greater demand for power and current reduction
Engineers working on battery-powered device development are under greater pressure
to obtain a reduction in power and current consumption. As the recent technology trend
in low power IoT, M2M, wearables, etc. has significantly accelerated this pressure, there
is a need to reduce more unused power from existing devices. As a result, engineers are
forced to look into even component level dynamic current consumption, which is always
very difficult to measure especially for low-power devices used in IoT enabled products.
What makes wideband low-level current waveform measure-
ments so difficult?
1. Limited dynamic range
Time
For example, most of the battery-powered devices have low power status such as “sleep
state” or “standby state” that consume very little supply current such as less than 1
μA, while the “active state” usually requires more than 10 mA current. It is difficult to
measure such a wide dynamic range of currents with a single measurement.
Figure 1. Current waveform measurements:
limited dynamic range, large measurement noise
and limited bandwidth
2. Large measurement noise
Wide
bandwidth
High speed
sampling
Clamp-on type current probes are widely used, but measuring low-level current less
than 1 mA is always difficult due to the large noise floor. Using a shunt resistor and an
oscilloscope is very useful, but the minimum measurable current is limited due to the
noise floor and the voltage drop across the resistor.
3. Limited bandwidth
Low-level current waveform measurements with a certain level of resolution need a
tradeoff with bandwidth, otherwise wideband measurements may degrade the resolu-
tion. Using a multimeter or an ammeter is popular for high resolution measurements, but
not appropriate for wideband current measurements due to the lesser bandwidth. It is
also difficult to measure multiple ranges with the same wide bandwidth when you use a
custom measurement instrument built using standard rather than specialist parts.
Time
Wide
dynamic
range
Low
noise
floor
4. Multiple instruments required
Figure 2. Expected key requirements for wide-
band low-level current waveform measurements.
A multimeter is commonly used to measure the averaged “sleep state” current, while
the “active state” current can be captured using an oscilloscope. The total power and
current consumptions must be manually estimated from these results, but the data is not
always reliable and it can be time consuming to validate it.
As shown in Figure 2, engineers and researchers need a wideband low-level current
waveform measurement solution with a single instrument, simultaneously meeting
multiple key measurement requirements.
KEYSIGHT [ Keysight Technologies ]
