alexwhittemore/BURT-MK-II-DAQ — Issue #23: Make silkscreen note about series input resistor
Author: alexwhittemore
Created: 2011-11-14 21:48:59+00:00
State: open

The bridge digitizer can be used without additional protection provided the clocked filter board is in place - this filter chip, with vdd=5v, can withstand an input range extending past +3.3v, while its output won't source enough current to break the AD7685 at these higher voltages. However, without this filter board in place, a direct short of filt_in to filt_out on the sensor board will result in a free, high-current path from the powerful amplifier output to the ad7685. A pressure spike or other high input voltage source could then break the 7685.