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Sweep Modes and Input/Output Types
Measurement instruments use both internal (system) sweep and user sweep modes. This section describes each of these modes and the instruments that support sweep modes. For additional information on defining setups, refer to Simulation Types.
Sweep Types
The sweeping of a source for an instrument is controlled by the instrument or by IC-CAP. This applies only for the instrument to which the primary unit belongs. The primary unit is a unit with a sweep order 1. The instrument with the primary unit is called the primary instrument.
Internal (System) Sweep
A primary instrument can perform its internal sweep when the Use User Sweep option of that instrument is set to No. Some instruments, such as the HP 4271, cannot perform a sweep measurement and do not have this option. A spot measurement with the internal sweep option enabled is converted to a single point measurement with the user sweep. It is impossible to perform a single spot internal sweep. Internal sweep is much faster than the user sweep (described in the next section), but not all sweep types are supported by the internal sweep of a particular instrument.
User Sweep
When the Use User Sweep is Yes for a primary instrument, IC-CAP performs a set of spot measurements to make up a single sweep measurement. Even though all supported instruments except time-domain instruments perform spot measurement, instruments like Network Analyzers need to use the internal sweep for calibrated data. Most sweep types are possible with user sweep because IC-CAP controls each point directly. However, a user sweep is much slower than an internal sweep.
Multiple Instruments
When multiple instruments are involved in a measurement setup, non-primary sweep instruments use the user (spot-mode) sweep regardless of how the Use User Sweep option is set. The sweep capabilities of the primary sweep instrument and the nature of the measurement determine whether internal or user sweep is appropriate.
When the primary instrument has internal sweep capability and other instruments are only used for non-primary sweeps or constants, the internal sweep for the primary instrument is possible. This includes the case where a network analyzer sweeps its frequency as a primary sweep while a DC bias is given as a secondary sweep from some DC instruments.
When multiple instruments have to synchronize at each measurement point, the user sweep must be used because these instruments don't know about each other. Only in this fashion can IC-CAP control them properly. An example is to measure both S parameters and DC currents at each frequency point.
Supported Internal Sweeps
The following table and Table 9 list the inputs, outputs, and internal sweeps that are possible with each instrument, with the following exceptions:
| • | Several time-domain pulse parameters can be extracted with Output T, like RISETIME. |
| • | The 8510A supports only LIN sweep. |
| • | 54120 Series includes HP 54121/122/123/124. |
| • | The 54122 does not support V-TDR Input, because the necessary pulse generator is not available in this instrument. |
| • | Two-port data is taken as S parameters, then converted by IC-CAP to other parameters. |
| • | The pulse generators have no measurement capability, thus no Output modes. |
For more information, refer to the individual instrument descriptions in the Reference manual.