Keithley 2600a series, Reference Manual, Page: 99 / 696

2600AS-901-01 Rev. B / September 2008 Return to Section Topics 4-5
Series 2600A System SourceMeter® Instruments Reference Manual Section 4: Source-Measure Concepts
CAUTION This maximum duty cycle equation is an approximation. In general, if the
duty cycle calculation yields a number > 90%, then DC under those
conditions should not cause the SourceMeter instrument to overheat.
However, if the calculation yields a number < 10%, the calculated duty cycle
should not be exceeded by more than 0.5% to avoid potential overheating.
Examples
Example 1:
Using a Model 2611A to charge a 5V battery with 1.5A, while operating at 50°C ambient
temperature; what is the maximum duty cycle?
Assuming the 20V range will be used to measure the voltage:
DC
MAX
≤ 47.0%
Example 2:
Using a Model 2602A to pulse 10A of current from a bias level of 500mA, into a very low
impedance (100 m
Ω
), while operating at 40°C ambient temperature; what is the maximum duty
cycle?
Assuming the 1V range will be used to measure the voltage:
DC
MAX
≤ 4.7%
Table 4-2
Model 2601A/2602A Maximum Duty Cycle equation constants
Constant 100mV range 1V range 6V range 40V range
P
CS
56 56 56 56
V
OA
18 18 18 55
Table 4-3
Model 2611A/2612A/2635A/2636A Maximum Duty Cycle equation constants
Constant 200mV range 2V range 20V range 200V range
P
CS
56 56 56 56
V
OA
40 40 40 220
DC
MAX
56 20
–
( )
40 5
( )
–
( )
0
( )
–
40 5
( )
–
( )
1.5
( )
------------------------------------------------------------------- 100
×
2
≤
DC
MAX
56 10
–
( )
18 0.1
( )
0.5
( )
–
( )
0.5
( )
–
18 10
( )
0.1
( )
–
( )
10
( )
------------------------------------------------------------------------------------------- 100
×
2
≤