8.1.1 Unipolar Operation Using DAC7811

To generate a positive voltage output, a negative reference is input to the DAC7811. This design is suggested instead of using an inverting amp to invert the output as a result of resistor tolerance errors. For a negative reference, VOUT and GND of the reference are level-shifted to a virtual ground and a –2.5-V input to the DAC7811 with an op amp.

Figure 28. Positive Voltage Output Circuit