N1419A Datasheet, PDF (6/16 Pages) Keysight Technologies – Femto/Picoammeter and Electrometer/High Resistance Meter

06 | Keysight | B2980A Series Femto/Picoammeter and Electrometer/High Resistance Meter - Data Sheet
Challenge 4: Verifying the integrity of
measurement cabling is essential for
accurate measurements, but conventional
instruments do not offer any means to
validate cable performance.
Solution 4. Optional software and dedicated accessories help
mitigate cabling complexities
When performing sensitive measurements making appropriate cabling connections is
often one of the more difficult challenges. Many factors can contribute to measurement
noise or instability, including incorrect cabling, poor cable quality and improper
guarding; however, determining the root cause of a measurement fixturing issue from
among all of these factors is not easy. Conventional instruments do not provide any
help to solve these types of issues and they typically only offer written guidance on
best practices. In contrast, the B2980A series has an available Setup Integrity Checker
function that can identify noise caused by external elements (cables, adapters, shields,
chambers, etc.) and display the information in tabular format on the front-panel GUI. As
shown below, the setup integrity checker function allows you to compare the noise level
of the instrument with no cables connected against the noise level with different setup
elements connected. By comparing the noise level standard deviation of different setup
elements side by side, you can easily determine the quality of cables and other setup
elements necessary for your measurements.
The B2980A series also has specialized accessories available to facilitate certain types
of measurements. For example, the N1413A High Resistance Meter Fixture Adapter
allows you to use the B2980A series with Keysight’s accessories for high resistance
measurement (such as the 16008B Resistivity Cell). A High Resistance Measurement
Universal Adapter (N1414A) is also available to simplify the cabling for high resistance
measurements.
Example showing how to use
the Setup Integrity Checker
Connector A
Take out DUT/sample
before start checking
Connector B
Original setup
Expected
noise level
with Cable A
Unexpected
noise level
with Cable B
Cable A
Cable B
Case,
Shield
Cable A
NOISE
Cable A
Cable B
Noise source finally isolated
How much faster is the
B2980A series’ settling
time?
When comparing instrument settling
times, you need to understand
how each instrument defines this
specification. Most conventional
instruments define settling time
as the time it takes to reach 10%
of the final value, whereas the
B2980A series uses a value of 0.1%.
By reducing dielectric absorption
(DA), the B2980A achieves a
faster settling time using the 0.1%
limit even in its lower measurement
ranges as shown below.
Final
value
± 0.1 % of final value
B2980A
settling to 0.1%
Conventional
electrometer’s
settling to 0.1 %
Time
20 pA range settling time
2 V step, 100 GΩ, 1 PLC
B2980A Conventional electrometer A
7
6 ^{The B2980A series is}
optimized for fast 0.1 %
5 _{settling time.}
4
3
2
1
0
10% of final value 0.1% of final value