Section 3: Functions and features Model 2651A High Power System SourceMeter® Instrument Reference Manual
3-68 2651A-901-01 Rev. A / March 2011
Enabling high-capacitance mode
Before enabling high-capacitance mode, note the following:
• It is important to read the previous section to understand the impact of high-capacitance mode.
• Test the DUT and the capacitor to determine the best current source and range of output voltages.
• The settling times can vary based on the DUT. It is important to test the limits of the DUT before you
use high-capacitance mode.
• Failure to test the DUT for the appropriate current source and output voltages can result in damage to or
destruction of the DUT.
• For optimal performance, do not continuously switch between normal mode and high-capacitance
mode.
• Before you charge the capacitor, start with 0 (zero) voltage across the capacitor.
• When high-capacitance mode is enabled, a minimum load capacitance of 100 nF is recommended. In
absence of this minimum load capacitance, overshoot and/or ringing may occur.
Front panel
To enable high-capacitance mode from the front panel:
1. Press the CONFIG key, then select SRC > HIGHC-MODE.
2. Select SRC-ENABLE > ENABLE. High-capacitance mode is enabled.
3. Push the ENTER key.
4. Press the EXIT (LOCAL) key to back out of the menu structure.
Command interface
Turning on High-C mode has the following effects on the SMU settings:
• smua.measure.autorangei is set to smua.AUTORANGE_FOLLOW_LIMIT and cannot be
changed.
• Current ranges below 1 μA are not accessible.
• If smua.source.limiti is less than 1 μA, it is raised to 1 μA.
• If smua.source.rangei is less than 1 μA, it is raised to 1 μA.
• If smua.source.lowrangei is less than 1 μA, it is raised to 1 μA.
• If smua.measure.lowrangei is less than 1 μA, it is raised to 1 μA.