Low-Power, Serial, 14-Bit DACs

with Voltage Output

______________________________________________________________________________________

13

Applications Information

Unipolar Output

Figure 6 shows the MAX5170/MAX5172 configured for

unipolar, rail-to-rail operation with a gain of +1.638V/V.

Table 2 lists the codes for unipolar output voltages. The

to introduce an offset voltage as shown in Figure 7 and

described in the

Offset and Buffer Configurations section.

Bipolar Output

Figure 8 shows the MAX5170/MAX5172 configured for

bipolar output operation. The output voltage is given by

the following equation (OS = AGND):

where N represents the numeric value of the DAC’s

reference. Table 3 shows digital codes and the corre-

sponding output voltage for Figure 8’s circuit.

VV

N

OUT

REF

=−









•

,

2

16 384

1

AGND

DGND

MAX5170

MAX5172

DAC

REF

OS

OUT

10k

10k

V-

V+

+5V/+3V

Figure 8. Bipolar Output Circuit

Figure 7. Setting OS for Output Offset

MAX5170

MAX5172

DAC

AGND

DGND

REF

OUT

OS

+5V/+3V

Table 2. Unipolar Code Table

(Circuit of Figure 6)

MAX5170

MAX5172

DAC

REF

OUT

OS

DGND

AGND

+5V/+3V

Figure 6. Unipolar Output Circuit (Rail-to-Rail)

Table 3. Bipolar Code Table

(Circuit of Figure 8)

DAC CONTENTS

MSB

LSB

ANALOG OUTPUT

11 1111 1111 1111

10 0000 0000 0001

10 0000 0000 0000

01 1111 1111 1111

00 0000 0000 0001

00 0000 0000 0000

ANALOG OUTPUT

0

00 0000 0000 0000

00 0000 0000 0001

01 1111 1111 1111

10 0000 0000 0000

10 0000 0000 0001

11 1111 1111 1111

DAC CONTENTS

MSB

LSB