Model 4200A-SCS Parameter Analyzer Reference Manual Section 13: LPT library function reference4200A-901-01 Rev. C / February 2017 13-83rangeXThis command selects a range and prevents the selected instrument from autoranging.Usageint rangei(int instr_id, double range);int rangev(int instr_id, double range);instr_id The instrument identification coderange The value of the highest measurement to be made (the most appropriate range forthis measurement is selected); if range is set to 0, the instrument autorangesDetailsUse the rangeX command to eliminate the time required by automatic range selection on ameasuring instrument. Because the rangeX command prevents autoranging, an overrange conditioncan occur (for example, when measuring 10 V on a 2 V range). The value 1.0e+22 is returned whenthis occurs.The rangeX command can also reference a source, because a source-measure unit (SMU) can beeither of the following:• Simultaneously a voltage source, voltmeter, and current meter.• Simultaneously a current source, current meter, and voltmeter.The range of a SMU is the same for the source and the measure commands.Compliance limits – When selecting a range below the limit value, whether it is explicitly programmedor the default value, an instrument temporarily uses the full scale value of the range as the limit. Thisdoes not change the programmed limit value, and if the instrument range is restored to a value higherthan the programmed limit value, the instrument again uses the programmed limit value. SeeCompliance limits (on page 3-3) for more information.When changing the instrument range, be careful not to overrange the instrument. For example, a testinitially performed on the 10 mA range with a 5 mA limit is changed to test in the 1 mA range with a1 mA limit. Notice that the limit is lowered from 5 mA to 1 mA to avoid overranging the 1 mA setting.When source mode of the SMU changes, the measure range may change. This change minimizesvariations in the SMU output level. The source mode of the SMU refers to its voltage sourcing orcurrent sourcing capability. Changing the source mode means using a command (such as forceX) tochange the SMU mode from forcing voltage to forcing current (or from forcing current to forcingvoltage). For example, if the SMU is programmed to force voltage (forcev), and then is programmedwith to force current (forcei), to ensure a consistent output signal, the previously programmedcurrent measure range may change. Make sure the correct measure range is set by sending therangeX command after switching the source mode. The commands that can change the sourcemode are asweepX, bsweepX, forceX, pulseX, searchX, and sweepX.
