6243/44 DC Voltage Current Source/Monitor Operation Manual
4.1.3 Driving Guard (6243 Only)
4-5
4.1.3
Driving Guard (6243 Only)
The DRIVING GUARD terminal outputs the voltage with the same electric potential as HI SENSE.
WARNING: When connecting a shielded leads as shown in Figure 4-4, be sure to avoid electric shock
because up to
110 V is applied to the shield.
4.1.4
Oscillation Prevention
If the DUT itself oscillates, a capacitance or an inductance exceeding the rated values is connected, the
6243/44 may oscillate (due to the stray capacitance and residual capacitance of the connection leads, scan-
ner, fixture, etc.).
Oscillation of the device and oscillation of the 6243/44 can be distinguished by the oscillation frequency.
Oscillation frequency of the 6243/44 cannot exceed 2 MHz.
4.1.4.1
SMU (Source Measurement Unit) Oscillation Prevention
(1) Reasons for oscillation
•
During voltage source and voltage limiter operation, oscillation may occur due to capacitive load.
•
During current source and current limiter operation, oscillation may occur due to inductive load.
(2) Procedure to stop oscillation
When oscillation occurs, the oscillation detecting circuit activates, indicates the fault and outputs in-
formation showing the oscillation status to the header and status byte of the measurement data. In this
case, remove the cause of oscillation by using the following procedure.
1. Check that values are within the maximum load capacitance and maximum load
inductance indicated in Chapter 9, “SPECIFICATIONS.”
2. Use the shortest connection leads(s) and check for oscillation.
3. If oscillation does not occur when the shortest connection leads(s) are used, con-
nect as shown in Figure 4-4 to reduce capacitance and inductance of the leads and
other parts.
4. If the shortest connection leads(s) do not stop oscillation, insert an allowable
resistor to the load as shown in Figure 4-6.
NOTE:
When using multiple power sources, one of the power sources may cause oscillation, if so, oscilla-
tion may be detected in the other power sources. In this case, use the procedures in steps 1 to 4
above to locate the power source to remove the oscillation.
