AD5761/AD5721

Data Sheet

Rev. C | Page 28 of 31

Table 24. Disable Daisy-Chain Bit Description

Bit Name

Description

DDC

DDC decides whether daisy-chain functionality is enabled or disabled for the device. By default, daisy-chain functionality is

enabled.

0: daisy-chain functionality is enabled for the device.

1: daisy-chain functionality is disabled for the device.

SOFTWARE DATA RESET

The AD5761/AD5721 can be reset via software to zero scale, midscale, or full scale (see Table 25). The value to which the device is reset is

specified by the PV1 and PV0 bits, which are set in the write to control register command (see Table 11 and Table 12).

Table 25. Software Data Reset Register

MSB

LSB

DB23

DB22

DB21

DB20

DB19

DB18

DB17

DB16

DB15 to DB0

0

Register address

Register data

0

0111

Don’t care

1

X means don’t care.

SOFTWARE FULL RESET

The device can also be reset completely via software (see Table 26). When the register address is set to 1111, the device behaves in a

power-up state, where the output is clamped to AGND and the output buffer is powered down. The user must write to the control register

to configure the device, remove the 1 kΩ resistor clamp to ground, and power up the output buffer.

The software full reset command is also issued when the DAC output range is reconfigured during normal operation.

Table 26. Software Full Reset Register

MSB

LSB

DB23

DB22

DB21

DB20

DB19

DB18

DB17

DB16

DB15 to DB0

0

Register address

Register data

0

1111

Don’t care

1

X means don’t care.

NO OPERATION REGISTERS

The no operation registers are ignored and do not vary the state of the device (see Table 27).

Table 27. No Operation Registers

MSB

LSB

DB23

DB22

DB21

DB20

DB19

DB18

DB17

DB16

DB15 to DB0

0

Register address

Register data

0

0000/0101/0110/1101/1110

Don’t care

1

X means don’t care.