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Power-supply considerations, Grounding and layout considerations – Rainbow Electronics MAX5355 User Manual

Page 14

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MAX5354/MAX5355

10-Bit Voltage-Output DACs
in 8-Pin µMAX

14

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Power-Supply Considerations

On power-up, the input and DAC registers are cleared
(set to zero code).

For rated MAX5354/MAX5355 performance, REF must
be at least 1.4V below V

DD

. Bypass V

DD

with a 4.7µF

capacitor in parallel with a 0.1µF capacitor to GND.
Use short lead lengths and place the bypass capaci-
tors as close to the supply pins as possible.

Grounding and Layout Considerations

Digital or AC transient signals on GND can create noise
at the analog output. Tie GND to the highest-quality
ground available.

Good printed circuit board ground layout minimizes
crosstalk between the DAC output, reference input, and
digital input. Reduce crosstalk by keeping analog lines
away from digital lines. Wire-wrapped boards are not
recommended.

DAC

V

OUT

V+

V-

+5V/+3.3V

R1 = R2 = 10k

± 0.1%

MAX5354
MAX5355

REF

R1

R2

FB

OUT

V

DD

GND

Figure 10. Bipolar Output Circuit

DAC

OUT

MAX5354
MAX5355

10k

26k

REF

V

DD

GND

+5V/

+3.3V

+5V/+3.3V

AC

REFERENCE

INPUT

500mVp-p

MAX495

Figure 11. AC Reference Input Circuit

DAC

MAX5354
MAX5355

REF

OUT

R

I

OUT

2N3904

V

L

FB

+5V/+3.3V

V

DD

GND

Figure 12. Digitally Programmable Current Source