1) Set the DMM for this measurement:
DMMSetFunction(nDmm, ESR);
(ESR = 100).
2) Set the Aperture to the desiered value:
DMMSetAperture();
(should be 160ms or greater)
3) The default test amplitude is 0.5V RMS. It is best to keep this value. If you must change it use
DMMSetDMMSetACVSource()
. (the frequency value entered is ingnored in this mode). Stimulus level
can be set between 30mV and 900mV RMS. Change in stimulus level with requires Open Compensation
DMMOpenCalACCaps()
.
4) Perform Open Compensation using
DMMOpenCalACCaps()
with open test leads. This operation is
only required onece. The parameter generates remain valid while the DMM is active.
5) Read the resistance using
DMMReadSR(nDmm, C, R)
. Entering the nominal value of C will improve
measurement accuracy. This calue can be a previously measured, or some nominal value. If C is not
known, set it to 0.0. The returned resistance value is stored at a location pointed to by R.
For shortest measurement time, measure the values of all capacitors associated with a network using the
Charge Balanced method (CAPS = 44) due to its superb accuracy and speed. Follow it with
DMMReadSR()
to measure all resistors associated with each network.
The
DMMSetSourceRes
() function can modify the source impedance of the 2064, which will effect the
measurement. It may be used with a reference RC network as a way to improve accuracy.
Figure 4-12. Measuring R in a series RC network..
4.12 Inductance Measurement (SMU2064)
The SMU2064 measures inductance using a precision AC source with a frequency range of 100Hz to
100kHz depending on selected range. Since inductors can vary greatly with frequency, you may wish to
override the default frequency and adjust the test frequency using
DMMSetInductFreq()
. Following an
inductnace measurement operation (
DMMRead, DMMReadNorm, DMMReadStr
), you may retrieve
the value of the inductor’s Q using
DMMReadInductorQ
. The inductor’s series equivalent resistnace
can also be read using the
DMMReadInductorR
function.
Signametrics
46
The use of a high quality coaxial or at least a shielded cable is highly recommended. For best accuracy,
perform the Open Terminal Calibration
DMMOpenTerminalCal
function within an hour of inductance
