Keithley 6485/E Digital-Multimeter, DMM, 6485/E データシート
製品コード
6485/E
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www.keithley.com
1.888.KEITHLEY
(U.S. only)
A Greater Measure of Confidence
•
Cost-effective low current
measurement solution
•
10fa resolution
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5½-digit resolution
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<200µV burden voltage
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up to 1000 readings/second
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built-in Model 485 emulation
mode
•
IEEE-488 and rs-232 interfaces
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analog output
The 5½-digit Model 6485 Picoammeter combines
Keithley’s expertise in sensitive current measure-
ment instrumentation with enhanced speed and
a robust design . With eight current measurement
ranges and high speed autoranging, this cost-
effective instrument can measure currents from 20fA
to 20mA, taking measurements at speeds up to 1000
readings per second .
The Model 6485’s 10fA resolution and superior
The Model 6485’s 10fA resolution and superior
sensitivity make it well suited for characterizing low
current phenomena, while its 20mA range lets it
measure currents high enough for applications such
as measuring 4-20mA sensor loops .
Although it employs the latest current measurement
Although it employs the latest current measurement
technology, it is significantly less expensive than
other instruments that perform similar functions,
such as optical power meters, competitive pico-
ammeters, or user-designed solutions . With a price that’s comparable to a general purpose DMM,
the Model 6485 makes picoamp-level measurements affordable for virtually any laboratory or
production floor .
low Voltage burden and Higher accuracy
While DMMs typically employ shunt ammeter circuitry to measure current, the Model 6485 is a feed-
While DMMs typically employ shunt ammeter circuitry to measure current, the Model 6485 is a feed-
back picoammeter . This design reduces voltage burden by several orders of magnitude, resulting in a
voltage burden of less than 200µV on the lower measurement ranges . The low voltage burden makes
the Model 6485 function much more like an ideal ammeter than a DMM, so it can make current
measurements with high accuracy, even in circuits with
very low source voltages .
successor to the Model 485
The Model 6485 builds on the strengths of one of
The Model 6485 builds on the strengths of one of
Keithley’s most popular picoammeters, the Model 485,
offering an additional 20mA measurement range, as well
as much higher measurement speeds . With a top speed
of up to 1000 readings per second, the Model 6485 is
the fastest picoammeter Keithley has ever made . It offers ten times greater resolution than the Model
485 on every range . A time-stamped 2500-reading data buffer provides minimum, maximum, and
standard deviation statistics . A built-in emulation mode simplifies upgrading existing applications
originally configured with a Model 485 . This emulation mode makes it possible to control the Model
6485 with any custom code written to control the Model 485 . Refer to the comparison table for
additional information .
Model 485
Model 6485
Current Ranges
2nA–2mA
2nA–20mA
Voltage Burden
200µV
200µV (1mV on
20mA range)
Reading Rate
3/s
1000/s
Digits
4½
5½
Analog Output
Yes
Yes
Battery Option
Yes
No
Storage Buffer
100 points
2500 points
When do you need a picoammeter?
Measuring low DC currents often demands a lot more than a digital
multimeter (DMM) can deliver. Generally, DMMs lack the sensitivity required
to measure currents less than 100nA. Even at higher currents, a DMM’s
input voltage drop (voltage burden) of hundreds of millivolts can make
accurate current measurements impossible. Electrometers can measure
low currents very accurately, but the circuitry needed to measure extremely
low currents, combined with functions like voltage, resistance, and charge
measurement, can increase an electrometer’s cost signifi cantly. The Model
6485 Picoammeter combines the economy and ease of use of a DMM with
low current sensitivity near that of an electrometer.
Measuring low DC currents often demands a lot more than a digital
multimeter (DMM) can deliver. Generally, DMMs lack the sensitivity required
to measure currents less than 100nA. Even at higher currents, a DMM’s
input voltage drop (voltage burden) of hundreds of millivolts can make
accurate current measurements impossible. Electrometers can measure
low currents very accurately, but the circuitry needed to measure extremely
low currents, combined with functions like voltage, resistance, and charge
measurement, can increase an electrometer’s cost signifi cantly. The Model
6485 Picoammeter combines the economy and ease of use of a DMM with
low current sensitivity near that of an electrometer.
6485
Picoammeter
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