The number of buses needed on a curve tracer depends on the tests and applications you want to run. There are 3 bus configurations for all our curve tracers you can choose from 2 buses, 4 buses, and 6 buses.
2 buses are used for continuity testing using unpowered curve tracing. This means the device will be in an unpowered state as the pins are swept with voltage and their characteristics measured. If you require powered curve tracing, you will need 4 buses.
4 buses are the minimum configuration for powered curve tracing with two buses available as power supplies. This allows the device in a powered state as the pins are curve traced. The 4-bus configuration is more versatile and capable than a 2-bus configuration with the ability to connect to power supplies and perform powered and unpowered curve tracing.
A 6-bus configuration allows for powered curve tracing and provides additional two buses which are specifically intended to serve as low impedance power supply voltages. This can free up drives three and four for use as curve tracing drives, or as additional power supplies for a device with a large amount of power supply voltages. These drives can be used for curve tracing, but their accuracy is low since they are intended as power supplies.
This provides a quick summary of the capabilities of the three different bus configurations. For more detail into the buses and configurations, check out this page.