Keithley 6430 User Manual

5-16 Source-Measure Concepts
Where within the boundaries the SourceMeter operates depends on the load (DUT) that is
connected to the output. Figure 5-8 shows operation examples for resistive loads that are 2kΩ
and 800Ω, respectively. For these examples, the SourceMeter is programmed to source 10V
and limit 10mA.
In Figure 5-8A, the SourceMeter is sourcing 10V to the 2kΩ load and subsequently mea-
sures 5mA. As shown, the load line for 2kΩ intersects the 10V voltage source line at 5mA.
Figure 5-8B shows what happens if the resistance of the load is decreased to 800Ω. The
DUT load line for 800kΩ intersects the current compliance limit line placing the SourceMeter
in compliance. In compliance, the SourceMeter will not be able to source its programmed volt-
age (10V). For the 800kΩ DUT, the SourceMeter will only output 8V (at the 10mA limit).
Notice that as resistance decreases, the slope of the DUT load line increases. As resistance
approaches infinity (open output), the SourceMeter will source virtually 10V at 0mA. Con-
versely, as resistance increases, the slope of the DUT load line decreases. At zero resistance
(shorted output), the SourceMeter will source virtually 0V at 10mA.
Regardless of the load, current will never exceed the programmed compliance of 10mA.

Keithley 6430 Specifications

General

Type	Sub-Femtoamp Remote SourceMeter
Compliance Voltage	200 V
Maximum Output Voltage	200 V
Maximum Output Current	100 mA
Compliance Limit	Programmable
Interface	GPIB, RS-232
Input Impedance	>10^14 Ω

Summary

Safety Precautions

3 Basic Source-Measure Operation

Basic Source-Measure Procedure

Details setup for source-measure operations: function, values, limits, and output control.

5 Source-Measure Concepts

Compliance limit

Discusses compliance limits, values, and determination.

Operating boundaries

Covers voltage/current boundaries for source, sink, I-source, V-source, and source-measure modes.

6 Range, Digits, Speed, and Filters

Range and digits

Discusses available ranges, limits, manual/autoranging, and display resolution.

Speed

Filters

Provides information on 3-stage filtering to reduce reading noise.

7 Relative and Math

Math Operations

Details math (FCTN) operations: power, offset ohms, varistor, etc.

9 Sweep Operation

Configuring and Running a Sweep

Discusses setup, configuration, delay setting, and performing sweeps.

10 Triggering

Trigger Model

Discusses trigger model, layers, event detection, delay, and device action.

Configuring Triggering

Details how to configure various triggering aspects.

Remote Triggering

Details remote trigger model, commands, and basic triggering example.

11 Limit Testing

Types of Limits

Discusses three limit types: compliance, coarse, fine; summarizes grading and sorting modes.

Configuring and Performing Limit Tests

Describes configuration for limit tests and typical test procedure.

Remote Limit Testing

12 Digital I/O Port, Interlock, and Output Configuration

Digital I/O Port

Safety Interlock

Describes using Digital I/O Port as a safety interlock.

Front Panel Output Configuration

14 Status Structure

Programming and Reading Registers

Status Byte and Service Request (SRQ)

Explains programming Status Byte for SRQs and using serial poll to detect SRQs.

15 Common Commands

Command Summary

Lists IEEE-488.2 common commands used by the SourceMeter.

Command Reference

Provides detailed reference for common commands, excluding status structure.

16 SCPI Signal-Oriented Measurement Commands

Command Summary

Configuring Measurement Function

Provides detailed info on commands to configure measurement function.

Acquiring Readings

Describes commands to acquire post-processed readings, trigger, acquire, and single measurement.

17 SCPI Command Reference

18 Performance Verification

Verification Test Requirements

Recommended Test Equipment

Performing the Verification Test Procedures

Details restoring factory defaults, setting ranges, and output values.

Mainframe Verification

Covers procedures to verify mainframe accuracy alone.

19 Calibration

Recommended Calibration Equipment

Unlocking Calibration

Mainframe Calibration

Includes procedures to calibrate the mainframe without the Remote PreAmp.

20 Routine Maintenance

Line Fuse Replacement

Covers procedure and part numbers for replacing the line fuse.

Front Panel Tests

F Measurement Considerations

Floating measurement safety concerns

Discusses safety concerns for measurements up to 42V above chassis ground.

Low current measurements

Leakage currents and guarding

Explains reducing leakage currents using insulators, humidity control, and guarding.