F(Function) - Keithley 263 Instruction Manual

4.7.4
F (Function)
Purpose
Format
Parameters
Description
Default
Use to select the operating mode of the instrument.
Fn
FO Ohms
Fl Amps
F2 Volts
F3 Coul
F4 Amps V/R
F5 EXT INPUT
F6 Ladder
F7 Coul V/R
The four basic functions of the Model 263 are ohms (FO), amps, volts, and coulombs.
The Fl and F3 functions use the active current source. The output accuracy of this
source is not affected by burden voltage or loading, as long as compliance voltage
is not surpassed. The F4 and F7 functions use the passive (V/R) current source. This
current source has less offset, and is intended primarily for devices that have a very
low input voltage burden. The internal voltage source (F2) is used to source up to
f 19.9995V. An external source (up to 200V peak, lOOmA peak) can applied to EXT
INPUT on the rear panel of the Model 263. The F5 command is used to connect
the external source to the output of the Model 263.
The calibration "ladder" (F6) is used to calibrate the high ohms ranges (1OMQ -
lOOG62) of the Model 263. This calibration method uses PREAMP DUT voltage
readings of the Model 263 as calibration values instead of the actual resistance
measurements of the resistors. This method eliminates the need for precision equip-
ment that would be needed to accurately measure the high ohm resistors. By using
the "ladder", a single precision DMM (such as the Keithley Model 196 DMM) can
be used to calibrate the Model 263.
Upon power-up or after the instrument receives a DCL or SDC, the VOLTS func-
tion will be selected.
~o;~t'atIIIIIitIg Whenever an F command is sent, the instrument goes into standby,
PrOgramIllirlg OIJTPUT
70%; i i
Fix'
Y ! Select AMPS function.
Example
4-14