AD7541A: Using a current out MDAC in voltage switching mode

Document created by analog-archivist Employee on Feb 23, 2016
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In data sheets I have seen the circuits for OUT-Vin to 0, +Vin to - Vin, -Vin/2
to +Vin/2, but I need 0 to +Vin.
I guess that it is the typical use, so it is automatical without OAmp and
without feedback resistor, isn't it?


The circuit to obtain Vout from 0 to Vin is shown in figure 7 on page 6 of the
datasheet, in the section  entitled "Single Supply operation". Note that in
this case the applications circuit is turned around the opposite way: the fixed
reference is applied to OUT1, OUT2 is connected to ground and the output is
taken from Vref.

A buffer amplifier is required since the output resistance at Vref is typically
11kOHMS with a range from 7kOhms to 18kOhms.