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2182A Nanovoltmeter

2182A Nanovoltmeter
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The two-channel Model 2182A Nanovoltmeter is optimized for making stable, low noise voltage measurements and for characterizing low resistance materials and devices reliably and repeatably. It provides higher measurement speed and significantly better noise performance than alternative low voltage measurement solutions. The Model 2182A represents the next step forward in Keithley nanovoltmeter technology, replacing the original Model 2182 and offering enhanced capabilities including pulse capability, lower measurement noise, faster current reversals, and a simplified delta mode for making resistance measurements in combination with a reversing current source, such as the Model 6220 or 6221. • Make low noise measurements at high speeds, typically just 15nV p-p noise at 1s response time, 40–50nV p-p noise at 60ms • Delta mode coordinates measurements with a reversing current source at up to 24Hz with 30nV p-p noise (typical) for one reading. Averages multiple readings for greater noise reduction Flexible, Effective Speed/Noise Trade-offs The Model 2182A makes it easy to choose the best speed/filter combination for a particular application’s response time and noise level requirements. The ability to select from a wide range of response times allows optimizing speed/noise trade-offs. Low noise levels are assured over a wide range of useful response times, e.g., 15nV p-p noise at 1s and 40-50nV p-p noise at 60ms are typical. Figure 1 illustrates the Model 2182A’s noise performance. 150 • Synchronization to line provides 110dB NMRR and minimizes the effect of AC common-mode currents • Dual channels support measuring voltage, temperature, or the ratio of an unknown resistance to a reference resistor • Built-in thermocouple linearization and cold junction compensation Low noise measurements for research, metrology, and other low voltage testing applications Figure 1. Compare the Model 2182A’s DC noise performance with a nanovolt/micro-ohmmeter’s. All the data shown was taken at 10 readings per second with a low thermal short applied to the input. 1.888.KEITHLEY (U.S. only) www.keithley.com A Greater Measure of Confidence

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Low noise measurements for research, metrology, and other low voltage testing applications Ordering Information 2182A Nanovoltmeter Accessories Supplied 2107-4 Low Thermal Input Cable with spade lugs, 1.2m (4 ft). User manual, service manual, contact cleaner, line cord, lligator clips. a Low Thermal Input Cable with spade lugs, 9.1m (30 ft) Low Thermal Connector with strain relief Low Thermal Test Lead Kit Low Thermal Calibration Shorting Plug Single Fixed Rack Mount Kit Dual Fixed Rack Mount Kit Shielded GPIB Cable, 1m (3.2 ft) Shielded GPIB Cable, 2m (6.5 ft) Shielded RS-232 Cable, 1.5m...

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cancels out any constant thermoelectric offsets, so the results reflect the true value of the voltage being measured. The improved delta mode for the Model 2182A and the Model 622X current sources uses the same basic technique, but the way in which it’s implemented has been simplified dramatically. The new technique can cancel thermoelectric offsets that drift over time (not just static offsets), produces results in half the time of the original technique, and allows the current source to control and configure the Model 2182A. Two key presses are all that’s required to set up the...

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LOW LEVEL MEASURE & SOURCE Low noise measurements for research, metrology, and other low voltage testing applications Three Ways to Measure Nanovolts DC nanovoltmeters. DC nanovoltmeters and sensitive DMMs both provide low noise DC voltage measurements by using long integration times and highly filtered readings to minimize the bandwidth near DC. Unfortunately, this approach has limitations, particularly the fact that thermal voltages develop in the sample and connections vary, so long integration times don’t improve measurement precision. With a noise specification of just 6nV p-p, the...

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Volts Specifications (20% over range) CHANNEL 1/CHANNEL 2 RATIO: For input signals ≥1% of the range, Ratio Accuracy = ±{[Channel 1 ppm of Reading + Channel 1 ppm of Range * (Channel 1 Range/Channel 1 Input)] + [Channel 2 ppm of Reading + Channel 2 ppm of Range * (Channel 2 Range/Channel 2 Input)]}. DELTA (hardware-triggered coordination with Series 24XX, Series 26XXA, or Series 622X current sources for low noise R measurement): Accuracy = accuracy of selected Channel 1 range plus accuracy of I source range. DELTA measurement noise with 6220 or 6221: Typical 3nVrms / Hz (10mV range)21. 1Hz...

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Measurement Characteristics A/D Linearity: ±(0.8ppm of reading + 0.5ppm of range). Front Autozero Off Error 10mV–10V: Add ±(8ppm of range + 500µV) for <10 minutes and ±1°C. NOTE: Offset voltage error does not apply for Delta Mode. Autozero Off Error 10mV: Add ±(8ppm of range + 100nV) for <10 minutes and ±1°C. 100mV–100V: Add ±(8ppm of range + 10µV) for <10 minutes and ±1°C. NOTE: Offset voltage error does not apply for Delta Mode. Input Impedance 10mV–10V: >10GW, in parallel with <1.5nF (Front Filter ON). 10mV–10V: >10GW, in parallel with <0.5nF (Front Filter OFF). 100V: 10MW ±1%. DC Input...

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