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 current 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.
To Next Page
Loading...
