AD5758 datasheet(33/72 Pages) AD

33 / 72 page

Data Sheet

AD5758

Rev. 0 | Page 33 of 72

AVSS Considerations

AVSS is the negative supply rail and has a range of −33 V to 0 V. As

in the case of AVDD1, AVSS must obey the maximum operating range

of |AVDD1 to AVSS| of 60 V. For bipolar current output ranges, the

maximum AVSS can be calculated as (IOUT_MAX × RLOAD) + IOUT foot-

room. For unipolar current output ranges, AVSS can be tied to

AGND (that is, 0 V). For unipolar voltage output ranges, the max-

imum AVSS is −2.5 V to enable sufficient footroom for the internal

voltage output circuitry. To avoid power supply sequencing issues, a

Schottky diode must be placed between AVSS and GND (the GND

supply must always be available).

AVDD2 Considerations

AVDD2 is the positive low voltage supply rail and has a range of 5 V

to 33 V. If only one positive power rail is available, AVDD2 can be

tied to AVDD1. However, to optimize for reduced power dissipation,

supply AVDD2 with a separate lower voltage supply.

VLOGIC Considerations

VLOGIC is the digital supply for the device and can range from 1.71 V

to 5.5 V. The 3.3 V VLDO output voltage can be used to drive VLOGIC.

AD5758 Datasheet(PDF) 33 Page - Analog Devices