Atec Keithley-6220-6221 - Manual (Page 4)

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www.keithley.com
1.888.KEITHLEY
(U.S. only)
A Greater Measure of Confidence
figure 4. The Model 6221 and the free
example start-up control software make it
easy to create complex waveforms by adding,
multiplying, stringing together, or applying
filters to standard wave shapes.
The Model 6221 can also expand the capabilities
of lock-in amplifiers in applications that already
employ them . For example, its clean signals and
its output synchronization signal make it an
ideal output source for lock-in applications such
as measuring second and third harmonic device
response .
Model 2182a Nanovoltmeter
The Model 2182A expands upon the capabilities
of Keithley’s original Model 2182 Nano volt-
meter . Although the Model 6220 and 6221 are
compatible with the Model 2182, delta mode and
differential conductance measurements require
approximately twice as long to complete with
the Model 2182 as with the Model 2182A . Unlike
the Model 2182A, the Model 2182 does not sup-
port pulse mode measurements .
Source Current
1/60 second (1/50 when operating off 50Hz power)
Programmable: 50 µs to 12ms
Measurement integration period
Measuring difference voltage eliminates
line frequency noise, DC offsets
Voltage measurement noise at line frequency
Measured response voltage
Pulsed measurement without line sync Line synchronized pulse measurements
figure 3. Measurements are line synchronized to minimize 50/60Hz interference.
• aPPlICaTIoNs of
622X/2182a CoMbINaTIoN:
• Easy instrument coordination and
intuitive example software simplifies
setup and operation in many
applications.
• Measure resistances from 10n W to
100M W. One measurement system
for wide ranging devices.
• Low noise alternative to AC
resistance bridges and lock-in
amplifiers for measuring resistances.
• Coordinates pulsing and
measurement with pulse widths as
short as 50µs (6221 only).
• Measures differential conduc-
tance up to 10× faster and with
lower noise than earlier solutions
allow. Differential conductance is
an important parameter in semi-
con ductor research for describing
density of states in bulk material.
• Delta mode reduces noise in low
resistance measurements by a factor
of 1000.
• For low impedance Hall measure-
ments, the delta mode operation of
the Model 622X/2182A combination
provides industry-leading noise
performance and rejection of contact
potentials. For higher impedance
Hall measurements (greater than
100M W), the Model 4200-SCS can
replace the current source, switching,
and multiple high impedance
voltage measurement channels. This
provides a complete solution with
pre-programmed test projects.
6220
6221
DC Current Source
AC and DC Current Source
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