QuadTech 1855 - Step Test; Null

Page 36 of 76 Interface
2.4.2 Step Test
The Step Test manually cycles through the test when [TRIGGER] is pressed. To access the Step
Test, press [MAIN INDEX] and [F2] = STEP TEST. The MEAS DISPLAY menu will appear.
Program the Test Voltage, Constant Current, Range, Trigger and Speed. Refer to paragraphs
2.5.1 through 2.5.7 for programming details.
1.0V
0.5mA
NEXT PAGE 1/2
2uA
Lc :
< MEAS DISPLAY: STEP TEST >
A
TEST V.
C.C.
RANGE
:
:
:
DISCHARGECHARGE TEST
Vm = 0.0V
INT
MEDIUM
NEXT PAGE 2/2
Lc :
< MEAS DISPLAY: STEP TEST >
A
TRIGGER
SPEED
:
:
DISCHARGECHARGE TEST
Vm = 0.0V
A
Figure 2-5: Step Test Parameters
2.4.3 Null
During the 1855 instrument Null process a correction is made (subtracted out) as the result of
lead leakage current and stored in instrument memory to be applied to ongoing measurements.
For maximum measurement accuracy it is recommended that the NULL function be performed
on the 1855 instrument after power up, any time the test parameters are changed and any time the
test leads or fixture is changed.
Using the output voltage set in the SEQ or STEP test, the Null function measures the leakage
current of each range (20mA – 2mA – 200uA – 20uA – 2uA) under open circuit conditions.
After setting test parameters in the SEQ or STEP tests, connect the test leads to the 1855 output
connectors. Do not connect the device under test. Press [MAIN INDEX] and [F3] = NULL
TEST. There are no settings for NULL TEST. Press [TRIGGER] and the 1855 instrument will
complete the null function.