The Parametric Measure capabilty of the RI7100 DB lines is the resource of choice for low current measurments. The standard parametric measure board provides nA resolution and 100nA accuracy. As of January 2003 A new parametric measure board has been introduced that enables measurements to below one nA with standard deviations of 20pA. See the Note: New Low Current Measurement Capability on Roos Instruments Testers. This note refers to the operation for both types of Parametric Measure boards.
The DB lines on RI7100's can be used to make low current leakage measurements down to nano-amp resolution. The DB lines are limited to 2 mA total current however.
1. The DB lines have three states On, Off, and Open. When they are on, they connect the device to the voltage set in the "V ON" button, When off, they connect to the voltage set in the "V OFF" button. When Open they float. In addition when they are open they can be measured by a precision DC measurement resource.
2. To make a current measurement, Go to the Static Digital tester resource and get these buttons: Measure Mode, Measure V Force, Meas I Limit, Current Meas MAX, Measure Current and Measure Pin
3. Set Measure Mode to IMEAS
4. Set MEASURE V FORCE to the voltage level you want to measure current in the presence of.
5. Set MEAS I LIMIT to the desired current limit (This limits the current)
6. Set CURRENT MEAS MAX to the max anticipated level (This sets the A/D for measure resolution). It is good practice to make this value the same as MEAS I LIMIT.
7. On the MEASURE PIN button, select the specific DB pin.
8. Set the specific DBX button to OPEN
Here is an example panel:
1.) Be careful how connect sequence and disconnect settings relate to the the turn on sequence with DB lines. Look at Delta Settings to see what is actually happening.
2.) It is possible if a DB resource is making a leakage measurement, it may be of the DB line charging or discharging decoupling capacitance instead of actual leakage.