Keithley 6482 - Remote Range and Digits Programming; Range and Digits Programming Example; Speed

4-4 Return to Section Topics 6482-901-01 Rev. A / August 2012
Section 4: Range, Digits, Speed, and Filters Model 6482 Dual-Channel Picoammeter / Voltage Source Reference Manual
Remote range and digits programming
Table 4-2 summarizes the commands necessary to control range and digits. See Section 16 for
more details on these commands.
Range and digits programming example
Table 4-3 shows a programming example for controlling range and digits. The Model 6482 is set
up as follows:
• Channel 1 autorange: ON
• Channel 1 upper range limit: 2 mA
• Channel 1 lower range limit: 200 nA
• Display digits: 5½
Speed
The Speed/Accuracy menu is used to set the integration time of the analog-to-digital converter
(period of time the input signal is measured). The integration time affects the usable digits, the
amount of reading noise, and the reading rate of the instrument. The integration time is specified in
parameters based on the number of power line cycles (NPLC), where 1 PLC for 60 Hz is 16.67 ms
(1/60) and 1 PLC for 50 Hz is 20 ms (1/50).
In general, the fastest integration time (FAST; 0.01 PLC) results in increased reading noise and
fewer usable digits. The slowest integration time (HI ACCURACY; 10 PLC) provides the best
common-mode and normal-mode noise rejection. In between settings are a compromise between
speed and noise. The default power-on speed setting is NORMAL
(1 PLC).
Table 4-2
Range and digits commands
Commands Description
:SENSe[1]:CURRent:RANGe <n>
:SENSe[1]:CURRent:RANGe:AUTO <state>
:SENSe[1]:CURRent:RANGe:AUTO:ULIMit <n>
:SENSe[1]:CURRent:RANGe:AUTO:LLIMit <n>
:SENSe2:CURRent:RANGe <n>
:SENSe2:CURRent:RANGe:AUTO <state>
:SENSe2:CURRent:RANGe:AUTO:ULIMit <n>
:SENSe2:CURRent:RANGe:AUTO:LLIMit <n>
:DISPlay:DIGits <n>
Select channel 1 manual amps range (n = range).
Enable or disable Channel 1 autorange (state = ON or OFF).
Set upper limit for Channel 1 autorange (n = range).
Set lower limit for Channel 1 autorange (n = range).
Select channel 2 manual amps range (n = range).
Enable or disable Channel 2 autorange (state = ON or OFF).
Set upper limit for Channel 2 autorange (n = range).
Set lower limit for Channel 2 autorange (n = range).
Set display digits (n = 4, 5, 6, or 7).
Table 4-3
Range and digits programming example
Command Description
*RST
:SOUR1:VOLT 10
:SENS1:CURR:RANG:AUTO ON
:SENS1:CURR:RANG:AUTO:ULIM 2e-3
:SENS1:CURR:RANG:AUTO:LLIM 200e-9
:DISP:DIG 5
:OUTP1 ON
:READ?
:OUTP1 OFF
Restore GPIB defaults.
Source 10 V on Channel 1.
Enable Channel 1 autorange.
2 mA upper range limit.
200 nA lower range limit.
5½ display digits.
Turn on output.
Trigger and acquire reading.
Turn off output.