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.