Datasheet

AD5755-1 Data Sheet

Rev. E | Page 36 of 52

DAC Control Register

The DAC control register is used to configure each DAC channel. The DAC control register options are shown in Table 20 and Table 21.

Table 20. Programming DAC Control Register

D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0

0 1 0 X

INT_ENABLE CLR_EN OUTEN RSET DC_DC OVRNG R2 R1 R0

X = don’t care.

Table 21. DAC Control Register Functions

Bit Description

INT_ENABLE

Powers up the dc-to-dc converter, DAC, and internal amplifiers for the selected channel. Does not enable the output. Can

only be done on a per channel basis. It is recommended to set this bit and allow a >200 µs delay before enabling the output

because this results in a reduced output enable glitch. See

Figure 30 and Figure 48 for plots of this glitch.

CLR_EN Per channel clear enable bit. Selects if this channel clears when the CLEAR pin is activated.

CLR_EN = 1, channel clears when the part is cleared.

CLR_EN = 0, channel does not clear when the part is cleared (default).

OUTEN Enables/disables the selected output channel.

OUTEN = 1, enables the channel.

OUTEN = 0, disables the channel (default).

RSET Selects an internal or external current sense resistor for the selected DAC channel.

RSET = 0, selects the external resistor (default).

RSET = 1, selects the internal resistor.

DC_DC Powers the dc-to-dc converter on the selected channel.

DC_DC = 1, power up the dc-to-dc converter.

DC_DC = 0, power down the dc-to-dc converter (default).

This allows per channel dc-to-dc converter power-up/power-down. To power down the dc-to-dc converter, the OUTEN and

INT_ENABLE bits must also be set to 0.

All dc-to-dc converters can also be powered up simultaneously using the DCDC_ALL bit in the main control register.

OVRNG

Enables 20% overrange on voltage output channel only. No current output overrange available.

OVRNG = 1, enabled.

OVRNG = 0, disabled (default).

R2, R1, R0 Selects the output range to be enabled.

Output Range Selected

0 0 0 0 V to 5 V voltage range (default).

0 0 1 0 V to 10 V voltage range.

0 1 0 ±5 V voltage range.

0 1 1 ±10 V voltage range.

1 0 0 4 mA to 20 mA current range.

1 0 1 0 mA to 20 mA current range.

1 1 0 0 mA to 24 mA current range.