DP7110, DP7118, DP7119, DP7123, DP7124, DP7125

6

Applications Information

The devices are intended for circuits requiring digitally

controlled adjustable resistance, such as LCD contrast

control, where voltage biasing adjusts the display contrast.

Alternative Positive LCD Bias Control

An op amp can be used to provide buffering and gain on

the output of the DP7110/DP7125. This can be done by

connecting the wiper output to the positive input of a

noninverting op amp as shown in Figure 9. Figure 10 shows

a similar circuit for the DP7119/DP7124.

Adjustable Gain

Figures 11 and 12 show how to use either a variable

resistor or a potentiometer to digitally adjust the gain of a

noninverting op amp configuration, by connecting the

device in series with a resistor to ground. The devices

have a low 5 ppm/ C ratiometric tempco that allows for a

very stable adjustable gain configuration over temperature.

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DP7110/DP7125

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DP7118/DP7123

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