–13–

AD7304/AD7305

REV. A

APPLICATIONS

The AD7304/AD7305 is inherently a 2-quadrant multiplying

D/A converter. That is, it can easily be set up for unipolar out-

put operation. The full-scale output polarity is the same as the

reference input voltage polarity.

In some applications it may be necessary to generate the full

4-quadrant multiplying capability or a bipolar output swing.

This is easily accomplished using an external true rail-to-rail op

amp, such as the OP295. Connecting the external amplifier with

two equal value resistors as shown in Figure 34 results in a full

4-quadrant multiplying circuit. In this circuit the amplifier pro-

vides a gain of two, which increases the output span magnitude

to 10 volts. The transfer equation of this circuit shows that both

negative and positive output voltages are created as the input

(2)

+5V

10k

10k

AD7304

REF

Figure 34. Four-Quadrant Multiplying Application Circuit