Keithley 2306 Quick Results Guide

12 Front panel operation
The pulsed response of a device is rarely a perfect square wave. Figure 7 shows the current
response of a typical GSM handset during the transmit portion of the data frame. Using the
built in auto-time feature with a trigger threshold of 0.2 amp and no trigger delay, the
Model 2306 will automatically set the HIGH integration time, denoted by T
H1
, to 533 µ s.
For this value of HIGH integration time, the effect of the current transient at the beginning
of the pulse is included in the measurement. Although in this example the effect of the
current transient on the measurement is small, the user can eliminate the effect of the
transient by adding a suitable amount of trigger delay. In this case, a delay of 100 µ s is
sufficient to eliminate the effect of transient, approximately 70 µ s, from the measurement.
Accordingly, the HIGH integration time, T
H2
, must be reduced, in this case 300 µ s was
chosen, so the integration time does not extend into a section of the pulse the user does not
want to measure.
Figure 7
Eliminating the effect of a current transient on a pulse current measurement
NOTE In Figure 7, a trigger delay of 100 µ s is used to eliminate the effect of a current
transient on the pulse current measurement.
Trigger Threshold 0.2 A
Trigger delay 100 µsec
~ 1500mA
T
H2
= 300µsec
T
H1
= 533µsec

Keithley 2306 Specifications

General

Brand	Keithley
Model	2306
Category	Power Supply
Language	English