Model 6485 Picoammeter Instruction Manual
Applications Guide
I-9
Figure I-5
Shielding a high impedance device
The cabling in the circuit also requires shielding. Capacitive coupling between an electro-
static noise source and the signal conductors or cables can be greatly reduced by surround-
ing those conductors with a grounded metal shield, as shown in
. With this
shield in place, the noise current generated by the electrostatic voltage source and the cou-
pling capacitance flows through the shield to ground rather that through the signal conduc-
tors.
Figure I-6
Electrostatic shielding
To summarize, error currents due to electrostatic coupling can be minimized by following
these guidelines:
A
+
-
6485
Picoammeter
Metal
Shield
R
V
HI
LO
HI
LO
V
Noise
current
Shield
Shield-to-cable
capacitance
Source-to-shield
capacitance
Electrostatic
voltage source
Ground-referenced
signal conductor
Ground
Содержание 6485
Страница 1: ...Model 6485Picoammeter Instruction Manual A G R E A T E R M E A S U R E O F C O N F I D E N C E ...
Страница 20: ......
Страница 24: ......
Страница 44: ...1 20 Getting Started Model 6485 Picoammeter Instruction Manual ...
Страница 66: ...3 6 Measurements Model 6485 Picoammeter Instruction Manual ...
Страница 138: ...9 20 Remote Operation Model 6485 Picoammeter Instruction Manual ...
Страница 159: ...11 CommonCommands ...
Страница 164: ...11 6 Common Commands Model 6485 Picoammeter Instruction Manual ...
Страница 165: ...12 SCPISignalOriented MeasurementCommands ...
Страница 190: ...14 12 SCPI Reference Tables Model 6485 Picoammeter Instruction Manual ...
Страница 214: ...16 14 Calibration Model 6485 Instruction Manual ...
Страница 219: ...A Specifications ...
Страница 221: ...B StatusandErrorMessages ...
Страница 227: ...C GeneralMeasurement Considerations ...
Страница 233: ...D DDCEmulationCommands ...
Страница 247: ...E ExamplePrograms ...
Страница 250: ...E 4 Example Programs Model 6485 Picoammeter Instruction Manual ...
Страница 251: ...F IEEE 488BusOverview ...
Страница 266: ...F 16 IEEE 488 Bus Overview Model 6485 Picoammeter Instruction Manual ...
Страница 267: ...G IEEE 488andSCPI ConformanceInformation ...
Страница 311: ......