# Keysight 34420A 7.5-Digit NanoVolt/Micro-Ohm Meter # Keysight 34420A 7.5-Digit NanoVolt/Micro-Ohm Meter ## Key Features At A Glance - 7½ digit resolution with 100 pV and 100 nΩ sensitivity for low-level measurements - 1.3 nVrms and 8 nVpp noise performance on the 1 mV range (2-minute observation, per datasheet) - Two-channel input with built-in low-noise programmable scanner for automated voltage comparisons - Built-in ratio and difference functions across Channel 1 and Channel 2 - Three resistance modes: standard, low-power, and voltage-limited for dry-circuit testing - Offset compensation to minimize thermal EMFs and associated errors - Direct temperature measurement for SPRT, RTD, thermistor, and thermocouple probes with ITS-90 conversion - RS-232 and GPIB interfaces with SCPI and Keithley 181 programming language support The Keysight 34420A is a high-sensitivity nanoVolt/micro-Ohm meter optimized for low-level measurements. It combines low-noise voltage measurements with resistance and temperature functions in a single benchtop instrument, providing 7½ digit resolution with 100 pV voltage sensitivity and 100 nΩ resistance sensitivity. The instrument is RoHS compliant and applies to serial numbers MY61000101 and SG61000101 onwards. The 34420A is designed to take the uncertainty out of low-level measurements. Low-noise input amplifiers and a highly tuned input protection scheme bring reading noise down to 8 nVpp on the 1 mV range over a 2-minute observation period. Combined with 7½ digits of resolution, selectable analog and digital filtering, 2 ppm basic 24-hour DC voltage accuracy, and a shielded copper pin connector, the instrument supports accurate, repeatable measurements for nanoVolt-class work. ValueTronics International stocks and supports the Keysight 34420A from our 20,000 sq ft secure warehouse at 1675 Cambridge Drive, Elgin, Illinois. Every nanoVolt-class instrument we list is inspected and performance-verified by our technicians before shipment, so the condition grade and specifications you see in the listing reflect what the instrument actually delivered on our bench — not a seller's description. We've supported customers across calibration labs, semiconductor characterization groups, and standards laboratories since 1992, and we back every unit with our standard performance warranty. ## Brand Heritage The 34420A traces to Hewlett-Packard's test and measurement heritage. HP spun off its T&M business as Agilent Technologies in 1999, and Agilent then transferred its electronic measurement business to Keysight Technologies in 2014. Instruments in this product family have carried the HP, Agilent, and Keysight brand marks across the lineage, with full software, accessory, and calibration support continuity through Keysight today. ## Accessories Supplied - 4 ft low thermal cable with copper spade lugs (34102A) - Low thermal shorting plug (34103A) - Kelvin clip set (11062A) - 4-wire shorting plug - User's manual - Service manual - Test report - Contact cleaner - Power cord - Calibration certificate ## Product Core & Specifications Accuracy Specifications ± (% of reading + % of range) Function Range Test current 24-hour 23 °C ± 1 °C 90 day 23 °C ± 5 °C 1 year 23 °C ± 5 °C Temperature coefficient 0 °C to 18 °C / 28 °C to 55 °C DC voltage 1.0000000 mV — 0.0025 + .0020 0.0040 + .0020 0.0050 + .0020 0.0004 + .0001 10.000000 mV — 0.0025 + .0020 0.0040 + .0002 0.0050 + .0003 0.0004 + .0001 100.00000 mV — 0.0015 + .0003 0.0030 + .0004 0.0040 + .0004 0.0004 + .00006 1.0000000 V — 0.0010 + .0003 0.0025 + .0004 0.0035 + .0004 0.0004 + .00004 10.000000 V — 0.0002 + .0001 0.0020 + .0004 0.0030 + .0004 0.0001 + .00002 100.00000 V — 0.0010 + .0004 0.0025 + .0005 0.0035 + .0005 0.0004 + .00005 Resistance 1.0000000 Ω 10 mA 0.0015 + .0002 0.0050 + .0002 0.0070 + .0002 0.0005 + .00002 10.000000 Ω 10 mA 0.0015 + .0002 0.0040 + .0002 0.0060 + .0002 0.0005 + .00001 100.00000 Ω 10 mA 0.0015 + .0002 0.0040 + .0002 0.0060 + .0002 0.0005 + .00001 1.0000000 kΩ 1 mA 0.0015 + .0002 0.0040 + .0002 0.0060 + .0002 0.0005 + .00001 10.000000 kΩ 100 µA 0.0015 + .0002 0.0040 + .0002 0.0060 + .0002 0.0005 + .00001 100.00000 kΩ 10 µA 0.0015 + .0003 0.0040 + .0004 0.0060 + .0004 0.0005 + .00002 1.0000000 MΩ 5 µA 0.0020 + .0003 0.0050 + .0004 0.0070 + .0004 0.0006 + .00003 DC Voltage Noise Range 2-minute RMS noise 2-minute peak-peak noise 24-hour peak-peak noise 1 mV 1.3 nVrms 8 nVpp 12 nVpp 10 mV 1.5 nVrms 10 nVpp 14 nVpp 100 mV 10 nVrms 65 nVpp 80 nVpp 1 V 100 nVrms 650 nVpp 800 nVpp 10 V 450 nVrms 3 µVpp 3.7 µVpp 100 V 11 µVrms 75 µVpp 90 µVpp Measurement Characteristics — DC Voltage Measurement method Continuously integrating multi-slope III A-D Converter A-D linearity 0.00008% of reading + 0.00005% of range Input resistance 100 V (Ch1 only): 10 MΩ ± 1%; 1 mV through 10 V: > 10 GΩ, in parallel with < 3.6 nF Input bias current < 50 pA at 25 °C Injected current < 50 nA pp at 50 or 60 Hz Input protection 150 V peak any input terminal to Channel 1 LO, continuous; Channel-to-channel switching error (typical): 3 nV Channel isolation Isolation between input channels > 10^10 Ω Earth isolation 350 V peak any input terminal to earth; Impedance from any input terminal to earth is > 10 GΩ and < 400 pF Maximum voltage Channel 1 LO to Channel 2 LO, 150 V peak Measurement Characteristics — Resistance Measurement method Selectable 4-wire or 2-wire ohms; Current source referenced to Channel 1 LO input Offset compensation Used on all ranges except 100 kΩ and 1 MΩ; Can be turned off if desired Protection 150 V peak Open circuit voltage For resistance and low power resistance < 14 V; 20 mV, 100 mV, 500 mV selectable clamp Measurement Characteristics — Temperature SPRT ITS-90 calibrated temperature with the range of -190 °C to +660 °C Thermocouple Type B, E, J, K, N, R, S, T | Range: -210 °C to 1820 °C Thermistor 5 kΩ | Range: -80 °C to 150 °C RTD 4-wire, 4.9 Ω to 2.1 kΩ; types: a = .00385 (DIN/IEC 751) and a = .00391; Range: -200 °C to 850 °C Measurement Noise Rejection 60 (50) Hz dc CMRR 140 dB ac CMRR 70 dB Operating Characteristics Function Digits Integration time Readings/s (60 Hz / 50 Hz) DCV thermocouple 7.5 200 plc .15 (.125) DCV thermocouple 7.5 100 plc .3 (.25) DCV thermocouple 6.5 20 plc 1.5 (1.25) DCV thermocouple 6.5 10 plc 3 (2.5) DCV thermocouple 5.5 1 plc 25 (20.8) DCV thermocouple 5.5 0.2 plc 100 (100) DCV thermocouple 4.5 0.02 plc 250 (250) Resistance 7.5 200 plc .075 (.062) **Important:** Maximum voltage: Channel 1 LO to Channel 2 LO, 150 V peak. Input protection is 150 V peak any input terminal to Channel 1 LO (continuous). Earth isolation is 350 V peak any input terminal to earth.Recommended pairing: use the 34102A low-thermal input cable with copper spade lugs and the 34103A low-thermal shorting plug — both called out in the datasheet's standard accessory list — to maintain the low-thermal-EMF connection environment required for nanoVolt-class measurements. **Please review the Manufacturer's Data Sheet to verify published specifications. Feedback on this webpage is always welcome — please reach out to your Test Architect at any time for questions or concerns. Thank you, we truly appreciate you being our customer.** ## Details - **Price:** 8706.0 USD - **Vendor:** Keysight - **Type:** Multimeter - **Tags:** Keysight, Keysight Technologies, Manufacturers, Meters & DAQ, Micro Ohmmeter, product_manual_group_3, Product_new ## Variants | Variant | Price | Available | |---------|-------|-----------| | Default Title | 8706.00 USD | In stock | ## Images - 34420A Keysight Technologies Micro Ohmmeter --- > Source: [ValueTronics](https://valuetronics.com/products/34420a-keysight-micro-ohmmeter-new) > Updated: 2026-05-30