Gamry Interface 5000, Руководство оператора

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Instrument Circuitry
56
Figure 6-6
One A/D Signal Chain in the Interface 5000
Notes for Figure 6-6:
•
This diagram shows one of three identical ADC channels. One channel is dedicated to measurement of
the potentiostat’s curren t signal, another is used to measure the voltage signal, and the third is switched
between several functions.
•
All three A/D converters are triggered simultaneously to start a conversion. This trigger and the pulse
updating the Scan DAC voltage are under the control of a hardware state-machine. This insures that all
waveform and data-acquisition timing is tightly controlled and reproducible point-to-point.
By default, the data-acquisition is synchronized with the system ’ s 300 kHz and 600 kHz power-supply-
switching frequencies, reducing noise caused by the power supply. Data-acquisition times that are a
multiple of 1.666 µs maintain this synchronization.
•
All analog signals are received differentially as shown here.
•
The 5 Hz, 1 kHz, 10 kHz, 200 kHz and 1.4 MHz filters are 2-pole Butterworth filters.