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Keithley 6485

Single-Channel Picoammeter with GPIB and RS-232 Interfaces

Brand: Keithley
Model No: 6485
Our Model No: 6485
Condition: NEW
PDF Document Icon Data Sheet (195 KB)


Product Features:

  • Cost-effective low current measurement solution
  • 10fA resolution
  • 5 1/2-digit resolution
  • Less than 200μV burden voltage
  • Up to 1000 readings/second
  • Built-in Model 485 emulation mode
  • IEEE-488 and RS-232 interfaces
  • Analog output


  • Beam monitoring and radiation monitoring
  • Leakage current testing in insulators, switches, relays, and other components
  • SEM beam current measurements
  • Galvanic coupling measurements
  • Optoelectronic device testing and characterization
  • Optical fiber alignment
  • Circuit test and analysis in DCLF circuits
  • Sensor characterization
  • I-V measurements of semiconductors and other devices
  • Nanoelectronic device characterization
  • Capacitor leakage
  • Teaching labs

The Keithley 6485 Picoammeter combines Keithley's expertise in sensitive current measurement instrumentation with enhanced speed and a robust design. With eight current measurement ranges and high speed autoranging, this costeffective instrument can measure currents from 20fA to 20mA, taking measurements at speeds up to 1000 readings per second.

The 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 technology, it is significantly less expensive than other instruments that perform similar functions, such as optical power meters, competitive picoammeters, or user-designed solutions. With a price that's comparable to a general purpose DMM, the 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 6485 is a feedback 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 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

Scaled Voltage Analog Output

This output allows the 6485 to transmit measurement results to devices like DMMs, data acquisition boards, oscilloscopes, or strip chart recorders.

220V Overload Protection

This high overload protection and a robust design let the 6485 withstand abusive overflows.

One-Touch Front Panel Design

Functions can be configured easily with the push of a button, without complicated function menus.

Built-In Trigger Link Interface

The Trigger Link interface simplifies synchronizing the 6485 with other instruments and voltage sources. This interface combines six independent selectable trigger lines on a single connector for simple, direct control over all instruments in a system.

RS-232 and IEEE-488 Interfaces

These interfaces make it easy to integrate the 6485 into automated test and measurement systems.

Display On/Off Switch

For research on light-sensitive components, such as measuring the dark currents of photodiodes, the front panel display can be switched off to avoid introducing light that could significantly reduce the accuracy of the results.

REL and LOG Functions

The 6485 can make relative readings with respect to a baseline value or display the logarithm of the absolute value of the measured current.

Resistance Calculations

The 6485 can calculate resistance by dividing an externally sourced voltage value by the measured current.

Rear Panel BNC Inputs

Inexpensive, easy-to-use BNC cables can be employed, rather than more APPLICATIONS expensive triax cables.

  • 1 - Single-Channel 5 1/2-Digit Picoammeter w/Line Cord
  • 1 - Low Noise Cable w/Male BNC Ends (4801)
  • 1 - Protective BNC Shield/Cap (CAP-18)
  • 1 - Banana Lead-to-Screw Terminal Adapter (CA-186-1B)
  • 1 - Certificate of Calibration
  • 1 - User Manual (P/N 6487-900-00)
  • 1 - Manual Addenda
  • 1 - Document CD
Model Description Buy Now Price
4802-10 Keithley 4802-10 3m BNC-Male-to-Unterminated Low Noise Cable for Models 6482, 6485, and 7158 Add to Cart


4803 Keithley 4803 15.2m BNC-Male-to-BNC-Female Low Noise Cable Kit for Models 6482, 6485, and 7158 Add to Cart


7754-3 Keithley 7754-3 .9m BNC-Male-to-Alligator-Clips Cable Add to Cart


8607 Keithley 8607 1m 1000V Banana Cables (x2) for Series 2400 and Models 6487 and 6517B Add to Cart


8501-2 Keithley 8501-2 2m Micro-DIN-Male-to-Micro-DIN-Male Trigger Link Cable Add to Cart


8503. Keithley 8503. 1m DIN Male-to-BNC Male Trigger Link Cable Add to Cart


CS-565 Tek Video CS-565 Connector Add to Cart


7078-TRX-BNC Keithley 7078-TRX-BNC 3-Lug Triax-to-BNC Adapter Add to Cart


4288-1 Keithley 4288-1 Single Fixed Rack Mount Kit Add to Cart


4288-2 Keithley 4288-2 Dual Fixed Rack Mount Kit for Models 2000, 2700, and 6487 Add to Cart


KPCI-488LPA Keithley KPCI-488LPA IEEE-488.2 Interface Module for PCI Buses Add to Cart


KUSB-488B Keithley KUSB-488B IEEE-488.2 USB-to-GPIB Interface Adapter for USB Ports Add to Cart


Model Description Buy Now Price
C/6485-3Y-17025 Keithley C/6485-3Y-17025 3-Year ISO 17025 Calibration Contract for Model 6485 Add to Cart


C/6485-3Y-DATA Keithley C/6485-3Y-DATA 3-Year Calibration Contract with Data Plan for Model 6485 Add to Cart


C/6485-3Y-STD Keithley C/6485-3Y-STD 3-Year STD Calibration Contract for Model 6485 Add to Cart


C/6485-5Y-17025 Keithley C/6485-5Y-17025 5-Year ISO 17025 Calibration Contract for Model 6485 Add to Cart


C/6485-5Y-DATA Keithley C/6485-5Y-DATA 5-Year Calibration Contract with Data Plan for Model 6485 Add to Cart


C/6485-5Y-STD Keithley C/6485-5Y-STD 5-Year STD Calibration Contract for Model 6485 Add to Cart


Gold Plans
Model Description Buy Now Price
6485-3Y-EW-STD Keithley 6485-3Y-EW-STD 3-Year Calibration Contract for Model 6485 Add to Cart


6485-5Y-EW-STD Keithley 6485-5Y-EW-STD 5-Year Calibration Contract for Model 6485 Add to Cart


6485-EW Keithley 6485-EW 1-Year Factory Warranty for Model 6485 Add to Cart


Model Description Price
6485-US Keithley 6485-US *US Government Edition* Single-Channel Picoammeter with GPIB & RS-232 Interfaces
GSA Advantage
GSA Contract GS-07F-0375T
Government-/GSA-Eligible Entities Only.
For GSA Price, Please Call
Direct: (339) 239-4066
See our GSA Listing
Datasheet: PDF Document Icon(195 KB)
Manual: PDF Document Icon(1.97 MB)
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