AD5380_15 datasheet(35/40 Pages) AD

35 / 40 page

Data Sheet

AD5380

Rev. D | Page 35 of 40

Figure 41. AVDD Power Supply Controlled by a Load Switch

Figure 42. DVDD Power Supply Controlled by a Load Switch

TYPICAL CONFIGURATION CIRCUIT

Figure 43 shows a typical configuration for the AD5380-5

when configured for use with an external reference. In the

circuit shown, all AGND, SIGNAL_GND, and DAC_GND pins

are tied together to a common AGND. AGND and DGND are

connected together at the AD5380 device. On power-up, the

AD5380 defaults to external reference operation. All AVDD

lines are connected together and driven from the same 5 V

source. It is recommended to decouple close to the device

with a 0.1 μF ceramic and a 10 μF tantalum capacitor. In this

application, the reference for the AD5380-5 is provided

externally from either an ADR421 or ADR431 2.5 V reference.

Suitable external references for the AD5380-3 include the

ADR3412 1.2 V reference. The reference should be decoupled at

the REFOUT/REFIN pin of the device with a 0.1 μF capacitor.

Figure 43. Typical Configuration with External Reference

Figure 44 shows a typical configuration when using the internal

reference. On power-up, the AD5380 defaults to an external

reference; therefore, the internal reference needs to be config-

ured and turned on via a write to the AD5380 control register.

Control Register Bit CR12 allows the user to choose the

reference value; Bit CR 10 is used to select the internal

reference. It is recommended to use the 2.5 V reference when

AVDD = 5 V, and the 1.25 V reference when AVDD = 3 V.

Figure 44. Typical Configuration with Internal Reference

Digital connections have been omitted for clarity. The AD5380

contains an internal power-on reset circuit with a 10 ms brown-

out time. If the power supply ramp rate exceeds 10 ms, the user

should reset the AD5380 as part of the initialization process to

ensure the calibration data gets loaded correctly into the device.

VIN1

ADP196

AD5380

EN AGND

AVDD

DVDD

VIN2

VOUT1

VOUT2

AGND

DGND

AVDD

DVDD

VIN1

ADP196

AD5380

EN AGND

DVDD

AVDD

VIN2

VOUT1

VOUT2

AGND

DGND

DVDD

AVDD

ADR431/

ADR421

AD5380-5

AVDD

DVDD

SIGNAL_GND

DAC_GND

DGND

VOUT39

VOUT0

AGND

REFOUT/REFIN

REFGND

0.1

F

0.1

F

0.1

F

AVDD

DVDD

AD5380

AVDD

DVDD

SIGNAL_GND

DAC_GND

DGND

VOUT39

VOUT0

AGND

REFOUT/REFIN

REFGND

0.1

F

0.1

F

0.1

F

AVDD

DVDD

AD5380 Datasheet(PDF) 35 Page - Analog Devices

AD5380 Datasheet(HTML) 35 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

Datasheet Download

Link URL