
F-16
Measurement Considerations
Model 2520 User’s Manual
Photodiode current measurement channels
shows the circuit model for the dual photodiode current measurement chan-
nels. Note that the bias circuit provides the bias voltage via the inner shield of the triax
cable. To minimize measurement error caused by noise and extraneous currents, use only
low-noise triaxial cables. See
“Generated currents,” page F-18
Figure F-16
Model 2520 photo current measurement channels with dual bias supplies
+
–
+
–
IN 1
14
Bias 1
Detector 1
IN 2
Bias 2
Detector 2
Chassis
Ground
Analog to
Digital
Converter
14
CLK
Bias 1
Bias 2
Analog to
Digital
Converter
Summary of Contents for 2520
Page 250: ...A Specifications ...
Page 254: ...B StatusandErrorMessages ...
Page 262: ...C DataFlow ...
Page 266: ...D IEEE 488BusOverview ...
Page 281: ...E IEEE 488andSCPI ConformanceInformation ...
Page 285: ...F MeasurementConsiderations ...
Page 308: ...G GPIB488 1Protocol ...
Page 312: ...H ExamplePrograms ...
Page 317: ...I ContinuousPulseMode ...