Overall Block Diagram
Figure 3-7 shows the overall block diagram of the 4349B.
The 4349B doesn't have a test voltage source, and an external voltage source must be supplied
for operation. The 4349B has four input channels, form which the test current
owing
through the DUT are input. The multiplexer switches four channels on a single measurement
trigger. Each V, which is proportional to the input I, is analog-to-digital converted. The CPU
calculates I from the converted data, then calculates the DUT's resistance R, by dividing the
measurement voltage by the measured current.
Note
The test voltage is data which must be input by the front-panel keys or through
GPIB interface. The 4349B itself has neither voltage output nor voltage
measurement capability.
3-20
Function Reference
Figure 3-7. 4349A Overall Block Diagram
4349B